Danfoss · VFD
VLT Micro Drive FC 51 Modbus register map
Default configuration
- Protocol
- RS485
- Port
- 502
- Unit ID
- 1
- Addressing
- 1-based
- Byte order
- Big endian
- Word order
- High word first
- Baud rate
- 19200
- Parity
- Even
- Data bits
- 8
- Stop bits
- 1
This device has an RS-485 interface. Reach it through a Modbus RTU-to-TCP gateway, configured with the factory serial settings above.
Register map
| Address | Count | Name | Type | Unit | Scale | Access |
|---|---|---|---|---|---|---|
| 50000 | 1 | Control word (FC profile) Control word according to the FC profile; bit definitions in section 7.1.1 of the Modbus RTU operating instruction. | UInt16 | - | 1 | RW |
| 50010 | 1 | Bus reference (FC profile) Speed reference written by the bus master. Scaling follows parameter 3-00/1-00 (reference/feedback unit). | Int16 | - | 1 | RW |
| 50200 | 1 | Status word (FC profile) Status word according to the FC profile; bit definitions in section 7.1.1 of the Modbus RTU operating instruction. | UInt16 | - | 1 | R |
| 50210 | 1 | Main actual value (FC profile) Main actual value sent with the status word; scaled according to parameter 3-00/1-00. | Int16 | - | 1 | R |
| 3020 | 2 | Minimum reference Minimum reference for the drive, in the reference unit selected in 3-00. | Int32 | - | 0.001 | RW |
| 3030 | 2 | Maximum reference Maximum reference for the drive, in the reference unit selected in 3-00. | Int32 | - | 0.001 | RW |
| 3100 | 1 | Preset reference Preset reference 0, in percent of the reference range. | Int16 | % | 0.01 | RW |
| 3110 | 1 | Jog speed Jog speed used by the Jog function. | UInt16 | Hz | 0.1 | RW |
| 3120 | 1 | Catch up/slow down value Percentage value added to or subtracted from the actual reference. | Int16 | % | 0.01 | RW |
| 3140 | 1 | Preset relative reference Relative reference in percent of the actual reference. | Int16 | % | 0.01 | RW |
| 3150 | 1 | Reference resource 1 Handling of the reference from resource 1; options are listed in the programming guide. | UInt16 | - | 1 | RW |
| 3160 | 1 | Reference resource 2 Handling of the reference from resource 2. | UInt16 | - | 1 | RW |
| 3170 | 1 | Reference resource 3 Handling of the reference from resource 3. | UInt16 | - | 1 | RW |
| 3400 | 1 | Ramp 1 type 0 = linear, 1 = S-ramp. | UInt16 | - | 1 | RW |
| 3410 | 2 | Ramp 1 ramp-up time Acceleration time from 0 to rated motor speed for ramp 1. | UInt32 | s | 0.01 | RW |
| 3420 | 2 | Ramp 1 ramp-down time Deceleration time from rated motor speed to 0 for ramp 1. | UInt32 | s | 0.01 | RW |
| 3500 | 1 | Ramp 2 type 0 = linear, 1 = S-ramp. | UInt16 | - | 1 | RW |
| 3510 | 2 | Ramp 2 ramp-up time Acceleration time for ramp 2. | UInt32 | s | 0.01 | RW |
| 3520 | 2 | Ramp 2 ramp-down time Deceleration time for ramp 2. | UInt32 | s | 0.01 | RW |
| 3800 | 2 | Jog ramp time Ramp time used by the Jog function. | UInt32 | s | 0.01 | RW |
| 3810 | 2 | Quick-stop ramp time Deceleration time used by the Quick Stop function. | UInt32 | s | 0.01 | RW |
| 4100 | 1 | Motor speed direction 0 = clockwise, 1 = counter-clockwise, 2 = both directions. | UInt16 | - | 1 | RW |
| 4120 | 1 | Motor speed low limit Lowest allowed output frequency. | UInt16 | Hz | 0.1 | RW |
| 4140 | 1 | Motor speed high limit Highest allowed output frequency. | UInt16 | Hz | 0.1 | RW |
| 4160 | 1 | Torque limit motor mode Maximum torque in motor mode, in percent of rated torque. | UInt16 | % | 1 | RW |
| 4170 | 1 | Torque limit generator mode Maximum torque in generator mode, in percent of rated torque. | UInt16 | % | 1 | RW |
| 4400 | 1 | Warning frequency low Low limit of the frequency warning range. | UInt16 | Hz | 0.1 | RW |
| 4410 | 1 | Warning frequency high High limit of the frequency warning range. | UInt16 | Hz | 0.1 | RW |
| 4500 | 2 | Warning current low Low limit of the current warning range. | UInt32 | A | 0.01 | RW |
| 4510 | 2 | Warning current high High limit of the current warning range. | UInt32 | A | 0.01 | RW |
| 4540 | 2 | Warning reference low Low limit of the reference warning range. | Int32 | - | 0.001 | RW |
| 4550 | 2 | Warning reference high High limit of the reference warning range. | Int32 | - | 0.001 | RW |
| 4560 | 2 | Warning feedback low Low limit of the feedback warning range. | Int32 | - | 0.001 | RW |
| 4570 | 2 | Warning feedback high High limit of the feedback warning range. | Int32 | - | 0.001 | RW |
| 4580 | 1 | Missing motor phase function 0 = off, 1 = on: trips when an output phase is missing. | UInt16 | - | 1 | RW |
| 4610 | 1 | Bypass speed from Start of the frequency band the drive avoids (compressor/fan resonance). | UInt16 | Hz | 0.1 | RW |
| 4630 | 1 | Bypass speed to End of the frequency band the drive avoids. | UInt16 | Hz | 0.1 | RW |
| 5100 | 1 | Terminal 18 digital input Function of digital input terminal 18; factory default 8 = start. | UInt16 | - | 1 | RW |
| 5110 | 1 | Terminal 19 digital input Function of digital input terminal 19; factory default 10 = reversing. | UInt16 | - | 1 | RW |
| 5120 | 1 | Terminal 27 digital input Function of digital input terminal 27; factory default 1 = reset. | UInt16 | - | 1 | RW |
| 5130 | 1 | Terminal 29 digital input Function of digital input terminal 29; factory default 14 = jog. | UInt16 | - | 1 | RW |
| 5150 | 1 | Terminal 33 digital input Function of digital input terminal 33; factory default 16 = preset reference. | UInt16 | - | 1 | RW |
| 5400 | 1 | Function relay Function of relay output 01/02. | UInt16 | - | 1 | RW |
| 5410 | 1 | On delay, relay Delay before the relay output switches on. | UInt16 | s | 0.01 | RW |
| 5420 | 1 | Off delay, relay Delay before the relay output switches off. | UInt16 | s | 0.01 | RW |
| 6100 | 1 | Terminal 53 low voltage Low voltage value of the analog input on terminal 53. | UInt16 | V | 0.01 | RW |
| 6110 | 1 | Terminal 53 high voltage High voltage value of the analog input on terminal 53. | UInt16 | V | 0.01 | RW |
| 6120 | 1 | Terminal 53 low current Low current value of the analog input on terminal 53. | UInt16 | mA | 0.01 | RW |
| 6130 | 1 | Terminal 53 high current High current value of the analog input on terminal 53. | UInt16 | mA | 0.01 | RW |
| 6140 | 2 | Terminal 53 low reference/feedback value Reference value that corresponds to the terminal 53 low voltage/current. | Int32 | - | 0.001 | RW |
| 6150 | 2 | Terminal 53 high reference/feedback value Reference value that corresponds to the terminal 53 high voltage/current. | Int32 | - | 0.001 | RW |
| 6190 | 1 | Terminal 53 mode 0 = voltage mode, 1 = current mode. | UInt16 | - | 1 | RW |
| 6220 | 1 | Terminal 60 low current Low current value of the analog input on terminal 60. | UInt16 | mA | 0.01 | RW |
| 6230 | 1 | Terminal 60 high current High current value of the analog input on terminal 60. | UInt16 | mA | 0.01 | RW |
| 6240 | 2 | Terminal 60 low reference/feedback value Reference value that corresponds to the terminal 60 low current. | Int32 | - | 0.001 | RW |
| 6250 | 2 | Terminal 60 high reference/feedback value Reference value that corresponds to the terminal 60 high current. | Int32 | - | 0.001 | RW |
| 6900 | 1 | Terminal 42 mode 0 = 0-20 mA, 1 = 4-20 mA. | UInt16 | - | 1 | RW |
| 6910 | 1 | Terminal 42 analog output Signal to be shown on analog output terminal 42. | UInt16 | - | 1 | RW |
| 6930 | 1 | Terminal 42 output min scale Minimum output value of terminal 42 in percent of the selected signal range. | UInt16 | % | 0.01 | RW |
| 6940 | 1 | Terminal 42 output max scale Maximum output value of terminal 42 in percent of the selected signal range. | UInt16 | % | 0.01 | RW |
| 8010 | 1 | Control site 0 = digital and control word, 1 = digital only, 2 = control word only. | UInt16 | - | 1 | RW |
| 8020 | 1 | Control word source 0 = none, 1 = FC RS485. | UInt16 | - | 1 | RW |
| 8030 | 1 | Control word timeout time Time before the control-word timeout function (8-04) acts. | UInt16 | s | 0.1 | RW |
| 8040 | 1 | Control word timeout function 0 = off, 1 = freeze output, 2 = stop, 3 = jogging, 4 = max speed, 5 = stop and trip. | UInt16 | - | 1 | RW |
| 8300 | 1 | Protocol 0 = FC, 2 = Modbus RTU. Factory default 0 (FC), so Modbus must be selected before the gateway can talk to the drive. | UInt16 | - | 1 | RW |
| 8310 | 1 | Address Bus address, 1-247 for Modbus. Factory default 1, which is the unit ID this seed uses. | UInt16 | - | 1 | RW |
| 8320 | 1 | FC port baud rate 0 = 2400, 1 = 4800, 2 = 9600, 3 = 19200, 4 = 38400 baud. Factory default 9600 for the FC protocol and 19200 when Modbus RTU is selected. | UInt16 | - | 1 | RW |
| 8330 | 1 | FC port parity / stop bits 0 = even parity, 1 stop bit (factory default); 1 = odd parity, 1 stop bit; 2 = no parity, 1 stop bit; 3 = no parity, 2 stop bits. | UInt16 | - | 1 | RW |
| 8350 | 1 | Minimum response delay Minimum delay between request and response. | UInt16 | s | 0.001 | RW |
| 8360 | 1 | Maximum response delay Maximum allowed delay between request and response; exceeding it causes a control-word timeout. | UInt16 | s | 0.001 | RW |
| 8940 | 1 | Bus feedback 1 Feedback value written over the bus. | Int16 | - | 1 | RW |
| 16000 | 1 | Control word (readout) Latest valid control word received over the serial port. | UInt16 | - | 1 | R |
| 16010 | 2 | Reference [unit] (readout) Total remote reference (sum of pulse, analog, preset, LCP, local bus and freeze reference). | Int32 | - | 0.001 | R |
| 16020 | 1 | Reference [%] (readout) Total remote reference in percent. | Int16 | % | 0.1 | R |
| 16030 | 1 | Status word (readout) Status word sent to the bus master. | UInt16 | - | 1 | R |
| 16050 | 1 | Main actual value [%] (readout) Main actual value sent with the status word. | Int16 | % | 0.01 | R |
| 16090 | 2 | Custom readout Customised readout from parameters 0-31/0-32. | Int32 | % | 0.01 | R |
| 16100 | 1 | Power [kW] Output power in kW. | UInt16 | kW | 0.001 | R |
| 16110 | 1 | Power [hp] Output power in hp. | UInt16 | hp | 0.001 | R |
| 16120 | 1 | Motor voltage Motor phase voltage. | UInt16 | V | 1 | R |
| 16130 | 1 | Frequency Output frequency. | UInt16 | Hz | 0.1 | R |
| 16140 | 1 | Motor current Motor phase current. | UInt16 | A | 0.01 | R |
| 16150 | 1 | Frequency [%] Output frequency as a percentage of 4-14 Motor Speed High Limit. | UInt16 | % | 0.1 | R |
| 16180 | 1 | Motor thermal Calculated thermal motor load. | UInt16 | % | 1 | R |
| 16300 | 1 | DC-link voltage DC-link voltage. | UInt16 | V | 1 | R |
| 16340 | 1 | Heat sink temperature Heat sink temperature. | UInt16 | °C | 1 | R |
| 16350 | 1 | Inverter thermal Calculated thermal load on the inverter. | UInt16 | % | 1 | R |
| 16360 | 1 | Inverter nominal current Continuous nominal inverter current. | UInt16 | A | 0.01 | R |
| 16370 | 1 | Inverter maximum current Intermittent maximum inverter current (150 %). | UInt16 | A | 0.01 | R |
| 16380 | 1 | SL controller state Number of the active smart-logic state. | UInt16 | - | 1 | R |
| 16500 | 1 | External reference Sum of all external references in percent. | Int16 | % | 0.1 | R |
| 16510 | 1 | Pulse reference Pulse input converted to a reference in percent. | Int16 | % | 0.1 | R |
| 16520 | 2 | Feedback [unit] Feedback value in the reference unit. | Int32 | - | 0.001 | R |
| 16600 | 1 | Digital input 18, 19, 27, 33 Bit field of the states of digital inputs 18, 19, 27 and 33. | UInt16 | - | 1 | R |
| 16610 | 1 | Digital input 29 State of digital input 29. | UInt16 | - | 1 | R |
| 16620 | 1 | Analog input 53 (V) Analog input 53 in voltage mode. | UInt16 | V | 0.01 | R |
| 16630 | 1 | Analog input 53 (mA) Analog input 53 in current mode. | UInt16 | mA | 0.01 | R |
| 16640 | 1 | Analog input 60 Analog input 60. | UInt16 | mA | 0.01 | R |
| 16650 | 1 | Analog output 42 Analog output 42. | UInt16 | mA | 0.01 | R |
| 16710 | 1 | Relay output [bin] Bit field of the relay outputs. | UInt16 | - | 1 | R |
| 16860 | 1 | FC port REF 1 Latest reference received over the FC port. | Int16 | - | 1 | R |
| 16900 | 2 | Alarm word Bit field of active alarms. | UInt32 | - | 1 | R |
| 16920 | 2 | Warning word Bit field of active warnings. | UInt32 | - | 1 | R |
| 16940 | 2 | Extended status word Extended status word. | UInt32 | - | 1 | R |
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Related guides
Notes
RS-485 device: reach it through a Modbus RTU-to-TCP gateway. The drive ships with the Danfoss FC protocol selected (8-30 = 0), so Modbus RTU (8-30 = 2) must be selected once. For Modbus the documented defaults are 8-32 = 19200 baud, 8-33 = even parity with 1 stop bit and 8-31 = address 1 - the 19200 8E1 block and unit ID this seed uses. Sources: Danfoss "VLT Micro Drive FC 51 Modbus RTU Operating Instruction" MG92B102 (https://files.danfoss.com/download/Drives/MG92B102.pdf), sections 4.1.12 (register addresses), 4.1.13 (parameter number x 10 = holding register; example 3-41 = register 3410), 5.1 and 5.2; names, types and conversion indices from the "VLT Micro Drive FC 51 Programming Guide" MG02C702 (https://files.danfoss.com/download/Drives/MG02C702.pdf), ch. 5.2 (-1 = 0.1, -2 = 0.01, -3 = 0.001). Addressing: the rows store the printed holding register numbers and the device is one_based, because 4.1.13 also states that register 3410 is addressed as 2809 (D51 hex) = 3409 in the data address field of the message. The four fixed FC-profile registers (50000 control word, 50010 reference, 50200 status word, 50210 main actual value) are a separate "Modbus Register Number" area with no worked frame: they are stored as printed, and a client must not apply the one_based offset to them. Their scale follows 3-00/1-00, so 50010/50210 carry no fixed factor. 32-bit parameters occupy two registers, high word first (HighFirst). Deliberate omissions: the coil map (16 control-word bits, 16 reference bits, status word, main actual value and coil 65 for EEPROM storage) - the operating instruction prints those numbers without saying whether they are zero- or one-based and its only coil example uses a different numbering, so the base cannot be settled; parameter groups 1-**, 2-**, 7-**, 13-**, 14-**, 15-** and 18-**, and the configuration-dependent PCD blocks 2810-2873 / 2910-2973.