PRA 400 (01)

About these operating instructions

• Warning! Read and understand all accompanying documentation, including but not limited to instructions, safety warnings, illustrations, and specifications provided with this product. Familiarize yourself with all the instructions, safety warnings, illustrations, specifications, components, and functions of the product before use. Failure to do so may result in electric shock, fire, and/or serious injury. Save all warnings and instructions for future reference.
  
• 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 accompanying documentation corresponds to the current state of the art at the time of printing. Please always check for the latest version on the product’s page on Hilti’s website. To do this, follow the link or scan the QR code in this documentation, marked with the symbol .
  
• Ensure that these operating instructions are with the product when it is given to other persons.
  

Explanation of symbols

Warnings

Symbols in the operating instructions

	Comply with the operating instructions
	Instructions for use and other useful information
	Dealing with recyclable materials
	Do not dispose of electric equipment and batteries as household waste
	Hilti Li‑ion battery
	Hilti charger

Symbols in illustrations

	These numbers refer to the illustrations at the beginning of these operating instructions.
	The numbers in illustrations refer to important work steps or to components important for the work steps. In the text, the corresponding numbers draw attention to these work steps or components, e.g. (3) .
	Item reference numbers are used in the overview illustration and refer to the numbers used in the key in the product overview section.
	This symbol is intended to draw your special attention to certain points for handling the product.

Product-dependent symbols

General symbols

	The product supports near-field communication (NFC) technology compatible with iOS and Android platforms.
	Direct current (DC)
	General warning symbol
	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.

General safety instructions, measuring tools

• Keep your workplace clean and well lit. Cluttered or poorly lit workplaces invite accidents.
  
• Do not operate the product in explosive atmospheres, such as in the presence of flammable liquids, gases or dust.
  
• Keep children and other persons clear when the product is in use.
  
• Use the product only within its specified limits.
  
• Comply with your national accident prevention regulations.
  

• Do not expose the product to rain or moisture. Penetrating moisture can cause short circuits, electrical shock, burns or explosions.
  
• Although the product is protected against the entry of moisture, it should be wiped dry before being put away in its transport container.
  

• Stay alert, watch what you are doing and use common sense when operating a measuring tool. Do not use a measuring tool while you are tired or under the influence of drugs, alcohol or medication. A moment of inattention while operating the measuring tool can result in serious personal injury.
  
• Avoid unusual body positions. Keep proper footing and balance at all times.
  
• Wear personal protective equipment. Wearing personal protective equipment reduces the risk of injury.
  
• Do not render safety devices ineffective and do not remove information and warning notices.
  
• Avoid accidental starting. Make sure that the measuring tool is switched off before connecting it to the battery and before picking it up or carrying it.
  
• Use the product and accessories in accordance with these instructions and in the way specified for this special type of tool. Take the working conditions and the work to be performed into account. Use of products for applications different from those intended could result in hazardous situations.
  
• Do not lull yourself into a false sense of security and do not flout the safety rules for measuring tools, even if you are familiar with the measuring tool after using it many times. Carelessness can result in serious injury within a fraction of a second.
  
• Do not use the measuring tool in the vicinity of medical devices.
  

• Use the product and accessories only when they are in perfect working order.
  
• Store measuring tools out of reach of children when not in use. Do not allow persons who are not familiar with the product or these instructions to operate it. Measuring tools are dangerous in the hands of inexperienced persons.
  
• Measuring tools need care and attention. Check that moving parts operate satisfactorily and do not jam, and make sure that no parts are broken or damaged in such a way that the measuring tool might no longer function correctly. Have damaged parts repaired before using the measuring tool. Many accidents are caused by poorly maintained measuring tools.
  
• Do not under any circumstances modify or tamper with the product. Changes or modifications not expressly approved by Hilti may restrict the user’s authorization to operate the product.
  
• Check the accuracy of the measuring tool before using it for important measurements, and if it has been dropped or subjected to other mechanical stresses.
  
• Due to the measuring principle employed, the results of measurements can be negatively affected by certain ambient conditions. These include, for example, the proximity of devices that produce strong magnetic or electro-magnetic fields, vibrations and temperature changes.
  
• Rapidly changing measuring conditions can falsify the results.
  
• When the product is brought into a warm environment from very cold conditions, or vice-versa, allow it to become acclimatized before use. Big differences in temperature can lead to incorrect operation and incorrect results.
  
• When adapters or accessories are used, make sure they are mounted securely.
  
• The measuring tool is designed for the tough conditions of jobsite use, but as with other optical and electrical products (e.g. binoculars, spectacles, cameras) it must be handled with care.
  
• The specified operating and storage temperatures must be observed.
  

Additional safety instructions

• Observe all safety instructions in these operating instructions and in the operating instructions of the Hilti rotating laser.
  
• Do not hold the laser receiver close to your ears. The volume of the laser receiver can cause injury and hearing loss.
  
• After switching on and while using the product, always pay attention to the information and warnings that appear on the display.
  
• Keep the detection area clean to avoid measurement errors. Do not touch the detection area with your fingers.
  
• Readings taken in the vicinity of reflective objects or surfaces, through panes of glass or similar materials may produce incorrect results.
  
• Make sure that no other laser measuring tool that can influence your measurements is in use in the vicinity.
  
• Use of the telescopic staff in the vicinity of overhead high voltage cables is not permissible.
  

Electromagnetic compatibility

• The tool may cause interference to other devices (e.g. aircraft navigation equipment).
  
• The tool may be negatively affected by powerful electromagnetic radiation, possibly leading to incorrect operation.
  

Careful handling and use of batteries

• Remove the batteries from the product if it is to remain unused for a lengthy period of time. Batteries can corrode and self-discharge during prolonged storage.
  
• Make sure that batteries are inaccessible to children.
  
• Do not mix old and new batteries. Always replace all batteries at the same time. Do not mix batteries of different makes or types.
  
• Do not use damaged batteries.
  
• Use only the battery type intended for this product. Use of other batteries may create a risk of injury and fire.
  
• When changing batteries, make sure that polarity is correct. There is a risk of explosion.
  
• Do not allow batteries to overheat and do not expose them to fire. Batteries can explode and release toxic substances.
  
• Do not attempt to charge non-rechargeable batteries.
  
• Do not solder batteries into the product.
  
• Do not discharge batteries by short-circuiting. Batteries can develop a leak, explode, catch fire and injure persons.
  
• Do not damage batteries and do not attempt to take batteries apart. Batteries can develop a leak, explode, catch fire and injure persons.
  

Product overview

1. Loudspeaker
   
2. Detection area
   
3. Marking notch
   
4. Right function button
   
5. MENU | OK button
   
6. Spirit level
   
7. On/off button
   
8. AUTO button
   
9. “Back” button
   
10. Left function button
    
11. Display (front)
    
12. Display (rear)
    
13. Distance, ouside edge of laser receiver to the marking notch
    
14. Battery compartment lock
    

Information shown in the display

1. Display icons, start screen
   
2. Connection to the rotating laser active/inactive
   
3. Connection to the tripod active/inactive
   
4. Display icons, receiver mode
   
5. Header
   
6. Selected accuracy
   
7. Indicator showing distance from laser plane in the selected unit
   
8. Unit, distance from zero
   
9. Position of the laser receiver relative to the height of the laser plane
   
10. Display icons, menu
    
11. Context-based display of the assignment of the function buttons
    

Intended use

Items supplied

Bluetooth

Product information

Inserting the batteries

1. Open the battery compartment.
   
2. Insert the batteries.
   
3. Close the battery compartment.
   

Pairing laser receiver with rotating laser and accessories

• Position the products close together. On both products, press the on/off buttons simultaneously and hold the buttons down for at least 3 seconds.
  
  • Successful pairing is confirmed by appearance of the symbol on and emission of an acoustic signal by the laser receiver.
    

Operation of the laser receiver

• Press the button on the laser receiver.
  
• The display of the PRA 400 laser receiver shows the rotating laser and the tripod in light gray visualization. As soon as connection to the rotating laser and/or tripod is established, the connected product is visualized black.
  
• The laser receiver has two function buttons enabling different operations (up/down, right/left, plus/minus) depending on the visualization shown on the display. The currently possible assignment of the function buttons is shown at the bottom edge of the display.
  
• Use the function buttons to select a symbol on the display of the laser receiver and press the button to confirm your choice.
  
• The symbol currently selected is shown with a black background.
  
• To return to the previous screen, press the button.
  

Using the laser receiver to detect the laser beam

1. Hold the laser receiver with the receiving window directly in the plane of the laser beam.
   
   • Reception of the laser beam is indicated by visual and acoustic signals.
     
   • The laser receiver shows the distance of the laser plane from the marking notch.
     
   • Depending on the situation, move the laser receiver or the rotating laser up or down until the rotation plane is aligned with the marking notch. The laser receiver shows the value "0".
     
2. While alignment is in progress hold the laser receiver steady or secure it in place. Make sure that there is a clear line of sight between laser receiver and rotating laser.
   

Menu options

	Horizontal mode
	Slope mode
	Vertical mode
	General settings
	Switch sleep mode on / switch sleep mode off
	Set the volume of the laser receiver (off, level 1/2/3)

	Switch off beam segments
	Automatic scan line function
	Activate / deactivate scan line and set width of scan line (point, 3 width settings, rotation)
	Move scan line (right/left by function buttons)
	Automatically transfer height with PRA 91 tripod.
	QR code → Automatically transfer height with PRA 91 tripod.

	Set slope
	Check slope
	Call up saved slope settings (favorites) or change settings
	Set slope with high precision
	QR code → link to overview of all slope functions

	Automatic vertical alignment
	Switch off one or more beam segments Use the right and left function buttons to select the beam segment of your choice. The rotating laser is shown in the viewing direction of the X axis. To switch the beam segment on or off, press the button. The active beam segments are shown in the header of the display.
	Automatic vertical alignment with surveillance function
	Automatic scan line function
	Activate / deactivate scan line and set width of scan line (point, 3 width settings, rotation)
	Move scan line (right/left by function buttons)
	QR code → link to overview of all functions in vertical mode

	Accuracy (5 stages) Select a stage in accordance with your requirements or, as applicable, the distance between rotating laser and laser receiver.
	Speed of rotation (3 stages)
	Activate/deactivate "protection against interfering light sources" mode
	Shock warning (off, stages 1/2/3)
	Service indicator
	More settings

	Deactivate automatic leveling (for manual slope adjustment)
	Change sequence of acoustic signals
	Firmware version, rotating laser/laser receiver
	Activate/deactivate QR codes
	Switch off one or more beam segments Use the right and left function buttons to select the beam segment of your choice. The rotating laser is shown in the viewing direction of the X axis. To switch the beam segment on or off, press the button. The active beam segments are shown in the header of the display.
	Scan line function
	Select the unit for the distance between the laser plane and the center mark and the unit for slope. Millimeters | degrees, percent or per mille Inches | degrees, percent or per mille (not available in all markets) Feet | degrees, percent or per mille (not available in all markets)

Operating the rotating laser

• → PR 40‑22
  
• → PR 40G‑22
  
• → PR 400‑22