Danfoss VLT HVAC User Manual (English)

Other manuals for Danfoss VLT HVAC

Questions and Answers:

G
George VargasAug 18, 2025
What to do if the motor is not running on my Danfoss VLT HVAC Controller?
- M
  Mr. Charles WashingtonAug 18, 2025
  If the motor of your Danfoss Controller is not running, check the service switch to ensure it is not open, and verify the motor connection. If you are using a 24 V DC option card, ensure mains power is applied to run the unit. If the LCP Stop is active, press [Auto On] or [Hand On] (depending on your operation mode) to start the motor. Also, ensure a valid start signal is applied and that the motor coast signal is not active by applying 24 V on terminal 27 or programming this terminal to No operation. Finally, verify the reference signal source is correctly programmed.
A
Aaron MitchellAug 20, 2025
Why is the Danfoss Controller display dark or not functioning?
- I
  imarksAug 20, 2025
  If the display of your Danfoss Controller is dark or not functioning, several issues could be the cause. First, check the input power source. Also, inspect the fuses to see if they are missing or open, or if a circuit breaker has tripped, and follow the recommendations provided. Ensure that the LCP has power; if not, replace the faulty LCP or connection cable. Check for any shortcuts on the control voltage (terminal 12 or 50) or at the control terminals, and wire the terminals properly. Make sure you are using the correct LCP (LCP 101 (P/N 130B1124) or LCP 102 (P/N 130B1107)). Adjust the contrast by pressing [Status] + [?]/[?]. If the display (LCP) is defective, replace the faulty LCP or connection cable. For an internal voltage supply fault or defective SMPS, contact the supplier.
A
Ashley TaylorAug 23, 2025
Why is the motor running in the wrong direction with my Danfoss VLT HVAC Controller?
- B
  Briana DillonAug 23, 2025
  If the motor of your Danfoss Controller is running in the wrong direction, the issue could be related to the motor rotation limit. Program the correct settings to resolve this. Alternatively, an active reversing signal might be the cause, so try deactivating it. A wrong motor phase connection could also be the problem.
T
Tyler PriceAug 26, 2025
What causes an intermittent display on a Danfoss Controller?
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  Tina WolfeAug 26, 2025
  If the display of your Danfoss Controller is intermittent, it may be due to an overloaded power supply (SMPS) caused by improper control wiring or a fault within the frequency converter. If the display stays lit, check the wiring for shorts or incorrect connections. If the display continues to cut out, follow the procedure for a dark display.
R
Roy PowersAug 27, 2025
How to fix if the motor is not reaching maximum speed on a Danfoss VLT HVAC?
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  Ms. Megan Lutz DDSAug 28, 2025
  If the motor is not reaching maximum speed with your Danfoss Controller, it could be due to incorrectly set frequency limits. Program the correct limits to resolve this. Another possible cause is an incorrectly scaled reference input signal. Ensure you program the correct settings for this as well.
J
Jennifer RobinsonAug 30, 2025
What causes open power fuses or circuit breaker trips in a Danfoss Controller?
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  William EdwardsAug 30, 2025
  If you are experiencing open power fuses or a circuit breaker trip with your Danfoss Controller, it could be due to a phase-to-phase short. Eliminate any shorts that are detected. Another possible cause is motor overload. Perform a startup test and verify the motor current is within specifications. If the motor current exceeds the nameplate full load current, the motor may need to run with a reduced load. Review the application specifications. Also, check for and tighten any loose connections.
M
Meghan OlsonSep 2, 2025
Why is the motor speed unstable on my Danfoss VLT HVAC Controller?
- T
  Terri HarrisonSep 2, 2025
  If the motor speed is unstable with your Danfoss Controller, it may be due to incorrect parameter settings. Check the settings in parameter group 1-6* Analog I/O mode. For closed loop operation, check the settings in parameter group 20-0* Feedback.

Danfoss VLT HVAC Specifications

General

Enclosure Rating	IP20, IP21, IP54, IP55, IP66
Storage Temperature Range	-25°C to +70°C
Output Voltage Range	0-100% of supply voltage
Communication Protocols	Modbus RTU, BACnet, Ethernet/IP, Profibus DP
Ambient Temperature Range	-10°C to +50°C (without derating)
Relative Humidity	5% to 95% non-condensing
Altitude	Up to 1000 m without derating
Cooling Method	Air cooled
Application	HVAC systems, Pumps, Fans, Compressors
Voltage Range	200-240 V, 380-500 V, 525-600 V
Frequency Range	0 Hz to 590 Hz