DD 250-CA

About this documentation

• Read this documentation before initial operation or use. This is a prerequisite for safe, trouble-free handling and use of the product.
  
• Observe the safety instructions and warnings in this documentation and on the product.
  
• Always keep the operating instructions with the product and make sure that the operating instructions are with the product when it is given to other persons.
  

Explanation of symbols used

Warnings

Warnings alert persons to hazards that occur when handling or using the product. The following signal words are used:

Symbols in the documentation

The following symbols are used in this document:

	Read the operating instructions before use.
	Instructions for use and other useful information
	Dealing with recyclable materials
	Do not dispose of electric equipment and batteries as household waste

Symbols in the illustrations

The following symbols are used in illustrations:

	These numbers refer to the corresponding illustrations found at the beginning of these operating instructions
	The numbering reflects the sequence of operations shown in the illustrations and may deviate from the steps described in the text
	Item reference numbers are used in the overview illustrations and refer to the numbers used in the product overview section
	This symbol is intended to draw special attention to certain points when handling the product.

Product-dependent symbols

"Must do" symbols

The following "must do" symbols are used:

	Wear eye protection
	Wear a hard hat
	Wear ear protection
	Wear protective gloves
	Wear protective footwear
	Wear light respiratory protection

Symbols on the product

The following symbols can be used on the product:

	Analysis data
	Hole-starting mode
	Rated speed under no load
	Alternating current
	Diameter
	Do not transport by crane
	Bluetooth
	Locking mechanism opened
	Locking mechanism closed
	The product supports wireless data transmission compatible with iOS and Android platforms.
	Protective ground
	If applied on the product, the product has been certified by this certification body for the US and Canadian markets according to the applicable standards.

Information notices

On the drill stand, base plate or diamond core drilling machine

	On the vacuum base plate Upper half of the image : An additional means of securing the drill stand must be employed when the machine is used for horizontal drilling with the vacuum securing method. Lower half of the image : Use of the vacuum securing method without an additional means of securing is prohibited for drilling in an upward direction.
	On the diamond core drilling machine Use of the water collection system in conjunction with a wet-type industrial vacuum extractor is a mandatory requirement for working overhead.
	On the diamond core drilling machine Operate the system only with a fully functional PRCD.

Product information

products are designed for professional users and only trained, authorized personnel are permitted to operate, service and maintain the products. This personnel must be specifically informed about the possible hazards. The product and its ancillary equipment can present hazards if used incorrectly by untrained personnel or if used not in accordance with the intended use.
The type designation and serial number are printed on the rating plate.

• Write down the serial number in the table below. You will be required to state the product details when contacting Hilti Service or your local Hilti organization to inquire about the product.
  Product information

  Diamond core drilling machine	DD 250-CA
  Generation	01
  Serial no.

Declaration of conformity

The manufacturer declares, on his sole responsibility, that the product described here complies with the applicable legislation and standards.
The technical documentation is filed here:
Hilti Entwicklungsgesellschaft mbH | Tool Certification | Hiltistrasse 6 | D-86916 Kaufering, Germany

General power tool safety warnings

WARNING Read all safety warnings, instructions, illustrations and specifications provided with this power tool. Failure to follow all instructions listed below may result in electric shock, fire and/or serious injury.
Save all warnings and instructions for future reference.
The term "power tool" in the warnings refers to your mains-operated (corded) power tool or battery-operated (cordless) power tool.
Work area safety

• Keep work area clean and well lit. Cluttered or dark areas invite accidents.
  
• Do not operate power tools in explosive atmospheres, such as in the presence of flammable liquids, gases or dust. Power tools create sparks which may ignite the dust or fumes.
  
• Keep children and bystanders away while operating a power tool. Distractions can cause you to lose control.
  

Electrical safety

• Power tool plugs must match the outlet. Never modify the plug in any way. Do not use any adapter plugs with earthed (grounded) power tools. Unmodified plugs and matching outlets will reduce risk of electric shock.
  
• Avoid body contact with earthed or grounded surfaces, such as pipes, radiators, ranges and refrigerators. There is an increased risk of electric shock if your body is earthed or grounded.
  
• Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the risk of electric shock.
  
• Do not abuse the cord. Never use the cord for carrying, pulling or unplugging the power tool. Keep cord away from heat, oil, sharp edges or moving parts. Damaged or entangled cords increase the risk of electric shock.
  
• When operating a power tool outdoors, use an extension cord suitable for outdoor use. Use of a cord suitable for outdoor use reduces the risk of electric shock.
  
• If operating a power tool in a damp location is unavoidable, use a residual current device (RCD) protected supply. Use of an RCD reduces the risk of electric shock.
  

Personal safety

• Stay alert, watch what you are doing and use common sense when operating a power tool. Do not use a power tool while you are tired or under the influence of drugs, alcohol or medication. A moment of inattention while operating power tools may result in serious personal injury.
  
• Use personal protective equipment. Always wear eye protection. Protective equipment such as a dust mask, non-skid safety shoes, hard hat or hearing protection used for appropriate conditions will reduce personal injuries.
  
• Prevent unintentional starting. Ensure the switch is in the off-position before connecting to power source and/or battery pack, picking up or carrying the tool. Carrying power tools with your finger on the switch or energising power tools that have the switch on invites accidents.
  
• Remove any adjusting key or wrench before turning the power tool on. A wrench or a key left attached to a rotating part of the power tool may result in personal injury.
  
• Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations.
  
• Dress properly. Do not wear loose clothing or jewellery. Keep your hair and clothing away from moving parts. Loose clothes, jewellery or long hair can be caught in moving parts.
  
• If devices are provided for the connection of dust extraction and collection facilities, ensure these are connected and properly used. Use of dust collection can reduce dust-related hazards.
  
• Do not let familiarity gained from frequent use of tools allow you to become complacent and ignore tool safety principles. A careless action can cause severe injury within a fraction of a second.
  

Power tool use and care

• Do not force the power tool. Use the correct power tool for your application. The correct power tool will do the job better and safer at the rate for which it was designed.
  
• Do not use the power tool if the switch does not turn it on and off. Any power tool that cannot be controlled with the switch is dangerous and must be repaired.
  
• Disconnect the plug from the power source and/or remove the battery pack, if detachable, from the power tool before making any adjustments, changing accessories, or storing power tools. Such preventive safety measures reduce the risk of starting the power tool accidentally.
  
• Store idle power tools out of the reach of children and do not allow persons unfamiliar with the power tool or these instructions to operate the power tool. Power tools are dangerous in the hands of untrained users.
  
• Maintain power tools and accessories. Check for misalignment or binding of moving parts, breakage of parts and any other condition that may affect the power tool’s operation. If damaged, have the power tool repaired before use. Many accidents are caused by poorly maintained power tools.
  
• Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control.
  
• Use the power tool, accessories and tool bits etc. in accordance with these instructions, taking into account the working conditions and the work to be performed. Use of the power tool for operations different from those intended could result in a hazardous situation.
  
• Keep handles and grasping surfaces dry, clean and free from oil and grease. Slippery handles and grasping surfaces do not allow for safe handling and control of the tool in unexpected situations.
  

Service

• Have your power tool serviced by a qualified repair person using only identical replacement parts. This will ensure that the safety of the power tool is maintained.
  

Drill safety warnings

Safety instructions for all operations

• Hold the power tool by insulated gripping surfaces, when performing an operation where the cutting accessory may contact hidden wiring or its own cord. Cutting accessory contacting a "live" wire may make exposed metal parts of the power tool "live" and could give the operator an electric shock.
  

Safety instructions when using long drill bits

• Never operate at higher speed than the maximum speed rating of the drill bit. At higher speeds, the bit is likely to bend if allowed to rotate freely without contacting the workpiece, resulting in personal injury.
  
• Always start drilling at low speed and with the bit tip in contact with the workpiece. At higher speeds, the bit is likely to bend if allowed to rotate freely without contacting the workpiece, resulting in personal injury.
  
• Apply pressure only in direct line with the bit and do not apply excessive pressure. Bits can bend causing breakage or loss of control, resulting in personal injury.
  

Diamond drill safety warnings

• When performing drilling that requires the use of water, route the water away from the operator’s work area or use a liquid collection device. Such precautionary measures keep the operator’s work area dry and reduce the risk of electrical shock.
  
• Operate power tool by insulated grasping surfaces, when performing an operation where the cutting accessory may contact hidden wiring or its own cord. Cutting accessory contacting a “live” wire may make exposed metal parts of the power tool “live” and could give the operator an electric shock.
  
• Wear hearing protection when diamond drilling. Exposure to noise can cause hearing loss.
  
• When the bit is jammed, stop applying downward pressure and turn off the tool. Investigate and take corrective actions to eliminate the cause of the bit jamming.
  
• When restarting a diamond drill in the workpiece check that the bit rotates freely before starting. If the bit is jammed, it may not start, may overload the tool, or may cause the diamond drill to release from the workpiece.
  
• When securing the drill stand with anchors and fasteners to the workpiece, ensure that the anchoring used is capable of holding and restraining the machine during use. If the workpiece is weak or porous, the anchor may pull out causing the drill stand to release from the workpiece.
  
• When securing the drill stand with a vacuum pad to the workpiece, install the pad on a smooth, clean, non-porous surface. Do not secure to laminated surfaces such as tiles and composite coating. If the workpiece is not smooth, flat or well affixed, the pad may pull away from the workpiece.
  
• Ensure there is sufficient vacuum before and during drilling. If the vacuum is insufficient, the pad may release from the workpiece.
  
• Never perform drilling with the machine secured by the vacuum pad only, except when drilling downwards. If the vacuum is lost, the pad will release from the workpiece.
  
• When drilling through walls or ceilings, ensure to protect persons and the work area on the other side. The bit may extend through the hole or the core may fall out on the other side.
  
• When drilling overhead, always use the liquid collection device specified in the instructions. Do not allow water to flow into the tool. Water entering the power tool will increase the risk of electric shock.
  

Additional safety instructions

Personal safety

• Do not tamper with or attempt to make alterations to the machine.
  
• The machine is not intended for use by debilitated persons who have received no special training.
  
• Keep the machine out of reach of children.
  
• Do not touch rotating parts. Switch the machine on only after it is in position at the workpiece. Touching rotating parts, especially rotating accessory tools, can result in injury.
  
• Avoid skin contact with drilling slurry.
  
• Dust from materials such as lead-based paint, certain types of wood and concrete/masonry/stone containing quartz, and minerals or metal can be harmful to health. Contact with or inhalation of the dust can cause allergic reactions and/or respiratory or other diseases among operators or bystanders. Certain kinds of dust such as oakwood and beechwood dust are classified as carcinogenic, especially in conjunction with additives for wood conditioning (chromate, wood preservative). Only specialists are permitted to handle material containing asbestos. Use as effective a dust removal system as possible. To achieve a high level of dust collection, use a suitable vacuum extractor of the type recommended by Hilti for wood dust and/or mineral dust and which is designed for use with this power tool. Make sure that the workplace is well ventilated. It is advisable to wear a dust mask appropriate for the type of dust generated. Comply with national regulations applicable to the materials you will be working with.
  
• The diamond core drilling machine and the diamond core bit are heavy. There is a risk of crushing parts of the body. The user and persons in the vicinity must wear suitable protective goggles, a hard hat, ear defenders, protective gloves and protective footwear while the machine is in use.
  

Power tool use and care

• Make sure that the machine is correctly secured to the drill stand.
  
• Always make sure that an end stop is installed on the drill stand as otherwise the safety-relevant end-stop function is not implemented.
  
• Check that accessory tools are compatible with the machine’s chuck/drive system and that they are installed and secured correctly.
  

Electrical safety

• Do not use extension cords with multiple power outlets powering two or more devices in operation at the same time.
  
• Operate the machine only when it is connected to an adequately rated power supply with a ground conductor.
  
• Before beginning work, check the working area (e.g. using a metal detector) to ensure that no concealed electric cables or gas and water pipes are present. External metal parts of the machine can become live, for example if you inadvertently damage electric wiring. This constitutes a serious risk of electric shock.
  
• Make sure that the supply cord cannot be damaged as the carriage advances.
  
• Never operate the machine without the accompanying PRCD (machines without PRCD: Never operate the machine without an isolating transformer). Test the PRCD each time before use.
  
• Check the machine’s supply cord at regular intervals and have it replaced by a qualified specialist if found to be damaged. If the machine’s supply cord is damaged it must be replaced with a specially prepared and approved supply cord available from Hilti Customer Service. Check extension cords at regular intervals and replace them if found to be damaged. Do not touch the supply cord or extension cord if it is damaged while working. Disconnect the supply cord plug from the power outlet. Damaged supply cords or extension cords present a risk of electric shock.
  
• Never operate the machine when it is dirty or wet. Dust, especially dust from conductive materials, or dampness on the surface of the power tool can, under unfavorable conditions, lead to electric shock. Have dirtied or dusty power tools checked at regular intervals by Hilti Service, especially if they are used frequently for working on conductive materials.
  
• Whenever you operate the diamond core drilling machine without DD AF-CA H, always install the cover over the AC supply for the DD AF-CA H. Water entering the power tool will increase the risk of electric shock.
  

Workplace

• Approval must be obtained from the site engineer or architect prior to beginning drilling work. Drilling work on buildings and other structures may influence the static equilibrium of the structure, especially when steel reinforcing bars or load-bearing components are cut through.
  
• If the drill stand has not been fastened correctly, always move the machine mounted on the drill stand all the way down in order to prevent the stand from falling over.
  
• Keep the supply cord, extension cord, water hose and vacuum hose away from rotating parts of the machine.
  
• Use of the water collection system in conjunction with a wet-type industrial vacuum extractor is a mandatory requirement for wet drilling overhead.
  
• Use of the vacuum securing method without an additional means of fastening is prohibited for drilling in an upward direction.
  
• An additional means of securing the drill stand must be employed when the machine is secured with the vacuum securing method (accessory) for horizontal drilling.
  

Product overviews

Diamond core drilling machine DD 250-CA

1. Multifunction display
   
2. Hole-starting mode operating button
   
3. Analysis data operating button
   
4. Rating plate
   
5. On/off switch
   
6. Supply cord cover
   
7. AC supply for DD AF-CA H (accessory)
   
8. Supply cord with PRCD
   
9. Water connection
   
10. Carrying handle (2x)
    
11. Carbon brush cover (2x)
    
12. Water flow regulator
    
13. Chuck
    
14. Gear selector
    

Drill stand DD-HD 30

1. Jack screw (accessory)
   
2. Cover
   
3. Rail
   
4. Leveling screw (3x)
   
5. Hole center indicator
   
6. Anchor
   
7. Base plate
   
8. Rating plate
   
9. Clamping spindle
   
10. Clamping nut
    
11. Brace
    
12. Carrying handle
    
13. End stop screw
    
14. Depth gauge (accessory)
    
15. Wheel assembly mount
    
16. Water collector holder (accessory)
    
17. Seal (accessory)
    
18. Water collector (accessory)
    
19. Sealing washer for water collector (accessory)
    

Carriage DD-HD 30

1. Hand wheel sleeve 1:1
   
2. Hand wheel sleeve 1:3
   
3. Eccentric pin (for locking the diamond core drilling machine)
   
4. Shear pin
   
5. Hand wheel
   
6. Leveling indicator (2x)
   
7. Carriage lock
   
8. Supply cord guide
   
9. Adapter interface for DD AF-CA H
   
10. Carriage play adjusting screw (4x)
    

Vacuum base plate (accessory)

1. Vacuum release valve
   
2. Vacuum hose connector
   
3. Wheel assembly mount
   
4. Pressure gauge
   
5. Vacuum seal
   
6. Leveling screw (4x)
   

Intended use

The product described is an electrically powered diamond core drilling machine. It is designed for the rig-based wet drilling of through-holes and blind holes in (reinforced) mineral materials. Hand-held use of the diamond core drilling machine is not permitted.

• Always use a drill stand when using the diamond core drilling machine. The drill stand must be sufficiently anchored in the base material by an anchor base plate or vacuum base plate.

• Do not use a hammer or other heavy object to adjustment the base plate.

• Operate the tool only when it is connected to a power source providing a voltage and frequency in compliance with the information stated on the rating plate.

• Comply with the safety rules and operating instructions for the accessories used.

Bluetooth^®

This product has Bluetooth.
Bluetooth is a wireless data transfer system by which the two Bluetooth-enabled products can communicate with each other over a short distance.
To ensure a stable Bluetooth connection there must be a clear line of sight between the connected devices.
Bluetooth functions of this productConsult the operating instructions of the paired device for detailed descriptions of the Bluetooth functions.

• Service and status messages of the paired Hilti devices are shown on the display of the diamond core drilling machine.
  
• Connection with a mobile terminal device via the Hilti ON!Track 3 app for service functions and for transmission of product-related analysis data.
  

Switching Bluetooth on or off

• To switch off, press and hold down the buttons and simultaneously for at least 10 seconds.
  
• To switch on, press the buttons and simultaneously.
  

Connecting productsThe pairing with a Bluetooth-compatible Hilti device is sustained until the diamond core drilling machine is paired to another Hilti device of the same type or Bluetooth is switched off. Pairing is also sustained even when the products are switched off and then on again; paired products always automatically re-establish their paired connection.

• To pair with a Bluetooth-compatible Hilti device or mobile device, with Bluetooth switched on simultaneously press the and buttons.
  

License
The Bluetooth^® word mark and the logo are registered trademarks and the property of Bluetooth SIG, Inc. and Hilti has been granted a license to use these trademarks.

Display symbols and explanation of the multifunction display on the diamond core drilling machine

For the following information to be displayed, the diamond core drilling machine must be ready for operation (plugged in and PRCD switched on).
The displays may vary depending on the gear selection and the type of application.

Start screen	The start screen is displayed when the diamond core drilling machine is supplied with power. The Bluetooth status, the personalized name and the serial number of the diamond core drilling machine are shown on the start screen. You can change the product name that appears on the screen in the Hilti ON!Track 3 app (default: 'Your name here ').
Spirit level	The diamond core drilling machine is not switched on. The display helps you to level the system and to align the drill stand when drilling at an angle. The display shows the alignment of the diamond core drilling machine symbolically and in degrees. Angular accuracy at room temperature: ±2°
Gear indicator	The diamond core drilling machine is running under no load. The display helps ensure that the gear engaged is suitable for the diamond core bit used. At top left, the display shows the gear engaged and in the center, the recommended core bit diameter range in millimeters and inches for this gear.
Hole-starting mode is active	The diamond core drilling machine is switched off or running under no load. This function makes it possible to start holes with low vibration when using large-diameter core bits. This function can be deactivated at any time by pressing the button again. This information is shown in the display only for a few seconds.
Remaining running time in hole-starting mode	The diamond core drilling machine is drilling and the hole-starting mode is active. The display shows the time remaining until the diamond core drilling machine automatically switches off. To protect the diamond core drilling machine, hole-starting mode is switched off automatically after a maximum of 2 minutes. The reading subsequently disappears from the display.
Hole-starting mode deactivated	Hole-starting mode has been deactivated. Speed and power of the diamond core drilling machine increase and drilling can proceed This information is shown in the display only for a few seconds.
Hole-starting mode cannot be activated	The diamond core drilling machine is drilling. The button for activating hole-starting mode was pressed while the diamond core drilling machine was under load or was in cool-down mode. This information is shown in the display only for a few seconds.
Drilling performance indicator: Contact pressure is too low	The diamond core drilling machine is drilling and the hole-starting mode is not activated. The information displayed helps ensure that the diamond core drilling machine is being operated in the optimal range. Background color: Yellow. Contact pressure is too low. Increase the contact pressure.
Drilling performance indicator: Optimum contact pressure	The diamond core drilling machine is drilling and the hole-starting mode is not active. The information displayed helps ensure that the diamond core drilling machine is being operated in the optimal range. Background color: Green. Contact pressure is at the optimum level.
For 120 V Rated current limit has been exceeded	The diamond core drilling machine is drilling and the hole-starting mode is not activated. Rated current has exceeded the limit of 20 A. Contact pressure is too high. Reduce the contact pressure.
Drilling performance indicator: Contact pressure is too high	The diamond core drilling machine is drilling and the hole-starting mode is not activated. The information displayed helps ensure that the diamond core drilling machine is being operated in the optimal range. Background color: Red. Contact pressure is too high. Reduce the contact pressure.
Status bar for information	The status bar displays various information regarding the machine’s current status, such as the gear engaged or the activated hole-starting mode.
Status bar for warning messages	The status bar displays various warnings regarding the tool's current status which do not result in the diamond core drilling machine stopping immediately.
Bluetooth ON	Bluetooth is activated in the basic setting. To switch off the Bluetooth function, press and hold down the buttons and simultaneously for 10 seconds with the motor switched off. This information is shown in the display only for a few seconds.
Bluetooth OFF	Bluetooth is deactivated. The diamond core drilling machine cannot be connected to additional device or accessories. To switch on the Bluetooth function, press the buttons and simultaneously with the motor switched off. This information is shown in the display only for a few seconds.
Connection has been established	The diamond core drilling machine is ready to connect to another device or accessory. To start the process of establishing the connection, simultaneously press the and buttons and hold them down for at least 1 second. The time frame for the connection to another device is 2 minutes. When the 2 minutes have expired, the connection process will be canceled. The paired connection between another device or accessory and the diamond core drilling machine is sustained until: The diamond core drilling machine is paired to a device or accessory of the same type. Bluetooth is switched off.
Connection interrupted	An existing Bluetooth connected to a device or accessory has been interrupted.
Analysis of running time	The display shows drilling time (diamond core drilling machine actually drilling) at the top and operating hours (diamond core drilling machine switched on) at the bottom. Both figures are shown in hours, minutes and seconds. To reset drilling time and all other analysis data, press the button and hold it down for a few seconds. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Analysis of operating behavior	This display shows contact pressure during drilling time as a percentage (%). This enables user behavior to be optimized. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Analysis of drilling direction	This display shows an evaluation of the drilling directions in %. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Analysis of gear selection	This display shows an evaluation of the duration of use of the respective gear in %. The arrow always points to the gear with the highest rate of use. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Analysis of use	This reading shows use of the diamond core drilling machine in manual mode and with use of an AF-CA in %. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Connected devices	This display provides an overview of all devices and accessories connected to the diamond core drilling machine. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Start connection setup	Start connection setup process at the diamond core drilling machine first and then at the device or accessory you want to connect. To start the process of establishing the connection, simultaneously press the and buttons and hold them down for at least 1 second. The information shown on the display disappears automatically after a few seconds or when you press the button. Pressing the again takes you to the next analysis data.
Gear selector not latched	The gear selector is in an intermediate position or is not correctly latched. Operate the gear selector until it latches completely.
Restart interlock	Maximum running time with hole-starting mode active has been exceeded; Fault in the power supply; The diamond core drilling machine has been overloaded; Overheated, water has entered the motor or the cooling running time has ended. Switch of the power tool is in I position while connection to the power supply being established.
Fault in the power supply (voltage too low)	Undervoltage occurred in the supply network. In the event of undervoltage, the diamond core drilling machine cannot be operated at full power. This information is shown in the display for a few seconds.
Overheating	The diamond core drilling machine has overheated and has switched off or is in the cooling mode. The indicator displays the time remaining until cooling down. If the diamond core drilling machine is still too hot after this time has elapsed, the remaining running time starts from the beginning again.
Time remaining until the carbon brushes must be replaced	The motor of the diamond core drilling machine is running and the carbon brush wear limit has almost been reached. The indicator displays the time remaining until the carbon brushes need to be replaced. The time remaining until the diamond core drilling machine automatically switches off is displayed in hours and minutes. This information is shown in the display for a few seconds.
Service display	The carbon brushes are worn and have to be replaced.
Running in after the carbon brushes have been replaced	The motor of the diamond core drilling machine is running. The carbon brushes have been changed and must be run in by letting the machine run under no load for at least 1 minute without interruption, in order to achieve the optimum service life. The indicator shows the time remaining until the run-in process has been completed.

Items supplied

Diamond core drilling machine, operating instructions.
Other system products approved for use with this product can be found at your local Hilti Store or at: www.hilti.group

Accessories and spare parts

Spare parts

Item number	Designation
51279	Hose connector
2006843	Carbon brushes 220-240 V
2104230	Carbon brushes 100-127 V

To help ensure safe and reliable operation, use only genuine Hilti accessories, spare parts and consumables.

Permissible core bit diameters for various items of equipment

It is essential to comply with the drilling directions approved for the various items of equipment.
For drilling upward, the use of a wet vacuum cleaner in combination with a water collection system is a mandatory requirement.

	DD 250-CA
Ø without accessories	12 mm … 300 mm
Ø with spacer	12 mm … 500 mm
Ø with water collection system and wet-type industrial vacuum cleaner	12 mm … 250 mm

Drill stand

	DD-HD 30
Weight	21.4 kg

Bluetooth

	DD 250-CA
Frequency band	2,400 MHz … 2,483 MHz
Maximum emitted transmission power	10 dBm

Noise information and vibration values in accordance with EN 62841

The sound pressure and vibration values given in these instructions have been measured in accordance with a standardized test and may be used to compare one power tool with another. They may be used for a preliminary assessment of exposure.
The data given represents the main applications of the power tool. However, if the power tool is used for different applications, with different accessory tools or is poorly maintained, the data may vary. This may significantly increase exposure over the total working period.
An accurate estimation of exposure should also take into account the times when the power tool is switched off, or when it is running but not actually being used for a job. This may significantly reduce exposure over the total working period.
Identify additional safety measures to protect the operator from the effects of noise and/or vibration, for example: Maintaining the power tool and accessory tools, keeping the hands warm, organization of work patterns.
Noise values

	DD 250-CA
Sound (power) level (L WA)	109 dB(A)
Uncertainty for the sound power level (K WA)	3 dB(A)
Sound pressure level (L pA)	93 dB(A)
Uncertainty for the sound pressure level (K pA)	3 dB(A)

Total vibration (vector sum of three directions), measured in accordance with EN 62841

Triaxial total vibration (vector sum of vibration) at the hand wheel (star handle) does not exceed 2.5 m/s ² (including uncertainty K), in accordance with EN 62841-3-6.

DD-HD 30: Setting up the drill stand and setting the drilling angle

1. Loosen the screw at the pivoting joint at the bottom end of the rail and the screw at the top end of the brace.
   
2. Adjust the rail to the desired angle.
   
   • The angle scale at the rear serves as an adjustment aid.
     
3. Retighten the two screws securely.
   

DD-HD 30: Locking the carriage on the drill stand

1. Pivot the carriage lock in the locked position.
   
   • The locking pin must engage in this position.
     
2. Slightly turn the hand wheel to ensure that the carriage is securely locked.
   

Fitting the hand wheel on the drill stand

1. Pull the black ring back to fit the hand wheel.
   
2. Fit the hand wheel onto the axle.
   

Securing the drill stand with an anchor

1. Fit the anchor that is suitable for the corresponding base material. Select the distance according to the base plate used.
   
   • Ideal distance from the hole center for DD-HD 30: 330 mm (13 in)
     
2. Screw the clamping spindle (accessory) into the anchor.
   
3. Place the drill stand over the spindle and align it. When using the DD-HD 30 drill stand, use the hole center indicator to help you align the drill stand. When a spacer is used, the drill stand cannot be aligned using the hole center indicator.
   
4. Screw the clamping nut on to the spindle but do not tighten it.
   
5. Level the base plate by turning the leveling screws. Use the leveling indicators for this purpose. Take care to ensure that the leveling screws make firm contact with the underlying surface.
   
6. Tighten the leveling screws evenly until the drill stand is securely fastened.
   
7. Check that the drill stand is secure.
   

Securing the drill stand by vacuum

1. Turn all the leveling screws until they project approx. 5 mm underneath the vacuum base plate.
   
2. Connect the vacuum connector on the vacuum base plate to the vacuum pump.
   
3. Locate the center point of the hole to be drilled. Draw a line from the center of the hole to be drilled in the direction in which the machine is to be positioned.
   
4. Make a mark on the line at the specified distance from the center of the hole to be drilled.
   Distance of marking
   
5. Switch on the vacuum pump and press and hold the vacuum release valve.
   
6. Line up the mark on the base plate with the line.
   
7. When the drill stand has been positioned correctly, release the vacuum release valve and press the base plate against the base material.
   
8. Use the leveling screws to level the base plate.
   
9. Check that the drill stand is secure.
   

Distance of markingSelect the distance to suit the base plate used.

Ideal distance of the mark on the vacuum base plate from the hole center	292 mm
Ideal distance of the mark on the combination base plate from the hole center	292 mm

DD-HD 30: Fastening the drill stand with the threaded spindle (accessory)

1. Remove the cover (with built-in end stop) from the top end of the rail.
   
2. Fit the cylindrical connector on the threaded spindle into the end of the rail on the drill stand.
   
3. Secure the threaded spindle by turning the eccentric pin.
   
4. Position the drill stand on the work surface.
   
5. Level the base plate by turning the leveling screws.
   
6. Secure the drill stand with the threaded spindle and tighten the threaded spindle.
   
7. Make sure that the drill stand is fastened securely.
   

DD-HD 30: Extending the rail (accessory) on the drill stand

1. Remove the cover (with built-in end stop) from the top end of the rail. Fit the cover on the extension rail.
   
2. Fit the cylindrical connector on the extension rail into the end of the rail on the drill stand.
   
3. Secure the extension rail by turning the eccentric pin.
   

DD-HD 30: Fitting the spacer (accessory)

1. Lock the carriage on the rail with the carriage lock.
   
2. Pull out the eccentric pin for locking the diamond core drilling machine on the carriage.
   
3. Place the spacer into the carriage.
   
4. Push the eccentric pin into the carriage as far as it will go.
   
5. Tighten the eccentric pin.
   
6. Check to ensure that the spacer is securely fastened.
   

DD-HD 30: Attaching the diamond core drilling machine to the drill stand

1. Lock the carriage on the rail with the carriage lock.
   
2. Pull out the eccentric pin for locking the diamond core drilling machine on the carriage.
   
3. Fit the diamond core drilling machine onto the carriage or the spacer.
   
4. Push the eccentric pin into the carriage or the spacer as far as it will go.
   
5. Tighten the eccentric pin.
   
6. Fasten the supply cord in the cord guide to the carriage cover.
   
7. Check to ensure that the diamond core drilling machine is securely fastened to the drill stand.
   

Fitting the water connection (accessory)

1. Connect the water flow regulator to the diamond core drilling machine.
   
2. Connect the water supply (hose connection).
   

installing the water collection system (accessory)

1. At the front of the drill stand, slacken the bottom screw at the rail.
   
2. Slip the water collector holder behind the screw from below.
   
3. Securely tighten the screw.
   
4. Position the water collector, with seal and water collector sealing disc installed, between the two movable arms of the holder.
   
5. Secure the water collector to the holder with the two screws.
   
6. Connect a wet-type industrial vacuum extractor to the water collector or establish a hose connection through which the water can drain away.
   

Setting the depth gage (accessory)

1. Turn the hand wheel until the core bit is in contact with the base material.
   
2. Set the desired drilling depth by adjusting the distance between the depth gage and the carriage.
   
3. Lock the depth gage in position.
   

Fitting the diamond core bit (BL chuck)

1. Lock the carriage on the rail with the carriage lock. Check to ensure that it is securely fastened.
   
2. Open the chuck by turning it in the direction of the "Open brackets" symbol.
   
3. From below, push the connection end of the diamond core bit into the chuck on the diamond core drilling machine, making sure that the teeth engage.
   
4. Close the chuck by turning it in the direction of the "Closed brackets" symbol.
   
5. Check that the diamond core bit is seated securely in the chuck.
   

Fitting the diamond core bit with an alternative type of chuck

1. Lock the drive spindle with a suitable open-end wrench.
   
2. Tighten the core bit with a suitable open-end wrench.
   

Selecting the speed

1. Set the selector switch to suit the diameter of the core bit used.
   
2. Turn the switch to the recommended setting while turning the core bit by hand at the same time.
   

Portable residual current device (PRCD)

1. Plug the diamond core drilling machine’s mains plug into an earthed/grounded power outlet.
   
2. Press the "I" or "RESET" button on the PRCD.
   
   • The indicator lights up.
     
3. Press the "0" or "TEST" button on the PRCD.
   
   • The indicator goes out.
     

4. Press the "I" or "RESET" button on the PRCD.
   
   • The indicator lights up.
     

Operating the diamond core drilling machine

1. Slowly open the water flow regulator until the desired volume of water is flowing.
   
2. Press the On/Off switch on the diamond core drilling machine to "I".
   
3. Release the carriage locking mechanism.
   
4. Turn the hand wheel until the core bit is in contact with the base material.
   
5. When beginning drilling, apply only light pressure, until the core bit has centered itself. Only increase the pressure afterwards.
   
6. Regulate the contact pressure while observing the drilling performance indicator.
   

Switching off the diamond core drilling machine

1. Connect the water flow regulator to the diamond core drilling machine.
   
2. Remove the diamond core bit from the hole.
   
3. Switch off the diamond core drilling machine.
   
4. Lock the carriage on the rail with the carriage lock.
   
5. Switch off the wet-type industrial vacuum cleaner (if used).
   

DD-HD 30: Detaching the diamond core drilling machine from the drill stand

1. Lock the carriage on the rail with the carriage lock.
   
2. Remove the supply cord from the cord guide on the carriage cover.
   

3. Loosen the eccentric pin for locking the tool on the carriage.
   
4. Pull out the eccentric pin.
   
5. Remove the diamond core drilling machine from carriage.
   
6. Push the eccentric pin into the carriage as far as it will go.
   

DD-HD 30: Adjusting the play between rail and carriage

1. Loosen the adjusting screws using a 5 mm hex key (do not remove the screws).
   
2. Using a 19 mm open-end wrench, turn the adjusting screws so that the rollers are pressed slightly against the rail.
   
3. Tighten the adjusting screws firmly. The carriage is correctly adjusted when it remains in position without a diamond core drilling machine fitted and moves down when a drilling machine is mounted.
   

Replacing the carbon brushes

1. Disconnect the diamond core drilling machine from the power supply.
   
2. Open the carbon brush covers on the left-hand and right-hand sides of the motor.
   
   • Take note of how the carbon brushes are installed and how the conductors are positioned.
     
3. Remove the worn carbon brushes from the diamond core drilling machine.
   
4. Fit the new carbon brushes, positioning them exactly the same as the old ones fitted previously.
   
   • Take care to avoid damaging the insulation on the indicator lead as you insert the brushes.
     
5. Screw on the carbon brush covers on the left- and right-hand side of the motor.
   
6. Run in the carbon brushes by letting the machine run under no load for at least one minute without interruption.
   
   After replacing the carbon brushes, the display Run-in after the carbon brushes have been replaced appears. The time bar shows the time remaining until the run-in process has been completed.
   If the minimum running-in time of one minute is not observed, the life of the carbon brushes will be greatly reduced.
   

The diamond core drilling machine is in working order

The diamond core drilling machine is not in working order

Recommended pretreatment for disposal of drilling slurry

1. Collect the drilling slurry (e.g. using a wet-type industrial vacuum extractor).
   
2. Allow the drilling slurry to settle and dispose of the solid material at a construction waste disposal site (adding a flocculant can accelerate the settling process).
   
3. Neutralize the left-over water (alkaline, pH > 7) by adding acidic neutralizing agent or diluting it with a large quantity of water before it is allowed to flow into the sewerage system.