• When you carry the laboratory power supply from a cold to a warm room, condensation may form. This poses
the risk of fatal injury due to electric shock. Thus, always allow the laboratory power supply to reach room
temperature before connecting it to the power outlet and turning it on and/or using it.
• Before and during use, make sure that your hands, shoes, clothing, the floor and the device itself are dry.
• Make sure that the insulation of the laboratory power supply, of the safety plugs, of all connected cables and
of the mains cable is not damaged or destroyed. Avoid using unprotected wires.
• The mains outlet must be located near to the device and be easily accessible.
• Never pull the mains plug from the socket by pulling at the cable. Always pull it from the mains socket using
the intended grips.
• Unplug the mains plug from the mains socket if you do not use the device for an extended period of time.
• Disconnect the mains plug from the mains socket in thunderstorms for reasons of safety.
• Make sure that the mains cable is not squeezed, bent, damaged by sharp edges or put under mechanical
stress. Avoid excessive thermal stress on the mains cable from extreme heat or cold. Do not modify the
mains cable. Otherwise the mains cable may be damaged. A damaged mains cable can cause a deadly
electric shock.
• Do not touch the mains cable if it is damaged. First, power down the respective mains socket (e.g. via the
respective circuit breaker) and then carefully pull the mains plug from the mains socket. Never use the
product if the mains cable is damaged.
• A damaged mains cable may only be replaced by the manufacturer, a workshop commissioned by the
manufacturer or a similarly qualified person, so as to prevent any danger.
• Never plug in or unplug the mains plug when your hands are wet.
• Never pour any liquids over electrical devices or put objects filled with liquid right next to the device. If liquid
or an object enters the interior of the device nevertheless, first power down the respective socket (e.g. switch
off circuit breaker) and then pull the mains plug from the mains socket. Do not operate the product anymore
afterwards, but take it to a specialist workshop.
• When using the device, do not carry any conductive metal objects or jewelry such as chains, bracelets,
rings, etc.
• Never leave the laboratory power supply unattended during use.
• Shield all connected units from malfunction and from excess voltage.
• Connecting several devices in in series may cause dangerous voltage which can pose a risk of fatal injury.
Heed the low voltage guideline.
• During use, the laboratory power supply produces heat. Never insert any objects into the product’s air vents
and do not obstruct ventilation in any way. The power supply is cooled primarily via convection. Thus, never
cover the laboratory power supply.
• In case safe operation is no longer guaranteed, cease use of the device immediately and shield it from
unintended use. Safe operation is no longer guaranteed when:
- the power supply is visibly damaged,
- the power supply no longer functions,
- the power supply was stored for an extended period under adverse conditions or
- if the product was damaged during transport.
• Do not use the laboratory power supply as a charger.
• The laboratory power supply is not approved for use on persons or animals.
• Opening any covers on the product or removing parts – unless this is possible by hand – may expose
voltage-carrying components. This poses the risk of fatal injury due to electric shock!
• Disconnect the device from the power outlet before opening it.
• Capacitors located in the laboratory power supply may still be charged even when the device is unplugged.
• Only use fuses of the specified type and rated current. The use of mended fuses is not permitted as this
poses a fire hazard!
• For installations in industrial facilities, follow the accident prevention regulations for electrical systems and
equipment of the government safety organization or the corresponding authority for your country.
• In schools and educational institutions, hobby and do-it-yourself workshops, the use of the laboratory power
supply must be supervised by trained staff.
• Please handle the product carefully. Jolts, impacts or a fall even from a low height can damage the product.
• Also observe the safety and operating instructions of any other devices which are connected to the product.
• Consult an expert when in doubt about operation, safety or connection of the device.
• Maintenance, modifications and repairs are to be performed exclusively by an expert or at a qualified shop.
• If you have questions which remain unanswered by these operating instructions, contact our technical
support service or other technical personnel.
Operating elements
1 LED display “A” for output current
2 LED display “V” for output voltage
3 Control dial “COARSE” for rough voltage adjustment
4 Control dial “FINE” for exact voltage adjustment
5 Plus socket for direct current output
6 Socket for ground (yellow-green)
7 Minus socket for direct current output
8 On/off switch
9 Control dial “CURRENT” for output current limit
10 LED display “CV” for output voltage regulation
11 LED display “CC” for output current regulation
12 Air vents
13 Fuse holder
14 Mains socket
Operating instructions
Version 04/16
BT-155 Laboratory power supply
Item no. 1389713
Intended use
This laboratory power supply functions as a potential-free source of power for the operation of low-voltage units. It has been
developed for universal use in the research, development, manufacturing, service and training fields. The units to be operated
are connected via the sockets on the front of the device. All operating controls and indicators have been neatly arranged to
simplify use. The corresponding power and voltage values are easily visible on the high-contrast LED display. The control dial
on the front of the device is used to set current and voltages values. The current consumption of a connected unit may not
exceed the maximum amperage as listed under technical data.
The laboratory power supply has a protection against overload and voltage reversal. The device conforms with protection class I.
It has been approved for connection only to a grounded power outlet and alternating voltage of 230 V/AC, 50 Hz.
Operation under adverse ambient conditions is not permitted. Adverse ambient conditions are defined as such:
• wetness or high humidity
• dust and flammable gases, vapors or solvents
• thunder storms and/or similar conditions (avoid strong electrostatic fields in general)
For safety and approval purposes (CE), you must not rebuild and/or modify this product. If you use the product for purposes
other than those described above, the product may be damaged. In addition, improper use can cause hazards such as short
circuiting, fire, electric shock etc. Read the instructions carefully and keep them. Make this product available to third parties
only together with its operating instructions.
This product complies with the statutory national and European requirements. All company names and product names are
trademarks of their respective owners. All rights reserved.
Delivery content
• Laboratory power supply
• Mains cable
• Operating instructions
Up-to-date Operating Instructions:
1. Open www.conrad.com/downloads in a browser or scan the displayed
QR code.
2. Select document type and language and enter the item number
into the search field. After submitting the query you can download
displayed records.
Explanation of symbols
This symbol indicates a health hazard, e.g. electric shock.
The exclamation mark indicates specific risks associated with handling, function and use.
The “arrow” symbol indicates special tips and operating information.
The product is intended for use only in indoor dry spaces, it may not become moist or wet.
This device is CE compliant and fulfills all applicable European guidelines.
Ground potential
Protective ground wire connection; do not loosen this screw.
Safety instructions
Read the operating instructions carefully and especially observe the safety information. If you do not
follow the safety instructions and information on proper handling in this manual, we assume no liability
for any resulting personal injury or damage to property. Such cases will invalidate the warranty/guarantee.
• The laboratory power supply conforms with protection class I and is suited for connection only to a grounded
power outlet (230 V/AC, 50 Hz). Make sure that the ground connection is not defective/interrupted as there
is a risk of fatal injury in case of malfunction.
• This product is not a toy, keep it out of the reach of children.
Children cannot recognize the dangers that may arise when handling electrical devices. Children may alter
settings or insert objects into the air vents on the lab power supply. This poses a risk of fatal injury due to
electric shock! Always use the product out of the reach of children.
• Do not leave packaging material lying around carelessly. These may become dangerous playing material
for children.
• The laboratory power supply may be set up and used only in dry, closed indoor spaces. It may not become
moist or wet. The power supply may not be exposed to extreme temperatures, direct sunlight, vibrations or
mechanical stress.
• Use the laboratory power supply only in mild climates, never in the tropics. Review the section on “Technical
data” to see the permitted ambient conditions for operation.
• Choose a location for the laboratory power supply that is stable, even, clean and sufficient in size.
• Do not have any open flames in the direct vicinity of the laboratory power supply and do not place any
containers with liquids on or near the device.
