A Danfoss VLT FC type code packs the drive series, power rating, phase, voltage class, enclosure, and options into one long positional string read field by field. The practical traps are that the power code is a kW key and not a current, that the FC 301 and FC 302 share one electrical rating, that the T5 class carries two different currents at the same kW, and that the FC 102 HVAC family does not yet decode a complete output current.
This guide explains what the Danfoss VLT Drive Decoder resolves: how to read the series and power code, how the voltage classes map (including the single-phase S2/S4 classes on the AQUA family), why Normal-Duty and High-Duty currents differ, and exactly which fields are reliable per family and which still require the design guide.
How to Read a VLT FC Type Code
Take FC-302P15KT5E20H1BGCXXXSXXXXA0BXCXXXXD0 apart:
- FC is the product group (Danfoss VLT FC drive).
- 302 is the series, which selects the family. 301/302 are the VLT AutomationDrive, 102 the VLT HVAC Drive, 202 the VLT AQUA Drive, and 051 the VLT Micro Drive FC 51.
- P15K is the power code: 15 kW. The letter K is the decimal point, so PK75 is 0.75 kW and P11K is 11 kW.
- T5 is the phase plus mains-voltage class: T = three-phase, 5 = the 380-500 V class.
- E20 is the enclosure (IP20), H1 the RFI/EMC filter, then brake, display, PCB coating, and the A/B/C/D option slots follow.
Dash separators are formatting, not data. The decoder reads the series digits to pick the family, then walks the remaining string by field order (token by token), not by absolute character position, because the source labels the same physical field with different position numbers per family.
The Power Code Is kW, Not a Current
This is the most common misread. The power-rating field is a kW code, used as a lookup key, not a current you can read off the digits:
- PKxx is a fractional kW: PK37 = 0.37 kW, PK75 = 0.75 kW.
- PnKm is n.m kW: P1K5 = 1.5 kW, P11K = 11 kW, P75K = 75 kW.
Danfoss is a kW-first manufacturer; the HP shown alongside is the published US equivalent from the same table, not a conversion the tool computed. The Normal-Duty and High-Duty output currents come from the matched ratings row. Match the motor full-load amps to the published output current for your duty, not to the HP label.
Voltage Classes, Including Single-Phase
The phase and mains-voltage characters resolve to a voltage class. T-classes are three-phase; S-classes are single-phase:
| Class | Phase | Range | Notes |
|---|---|---|---|
| T2 | 3-phase | 200-240 V | All families |
| T4 | 3-phase | 380-480 V | All families |
| T5 | 3-phase | 380-500 V | FC 301/302 only; distinct ND and HD |
| T6 | 3-phase | 525-600 V | FC 301/302, 102, 202 |
| T7 | 3-phase | 525-690 V | FC 301/302, 102, 202 |
| S2 | 1-phase | 200-240 V | FC 202 AQUA, FC 51 |
| S4 | 1-phase | 380-480 V | FC 202 AQUA single-phase |
The FC 202 AQUA publishes single-phase classes with different output currents than the three-phase classes at the same kW, so the decoder keys them separately. A power code at a voltage class that the family does not offer is rejected, not coerced onto a neighbour.
Normal Duty vs High Duty: Why Two Currents
For the AutomationDrive, AQUA and Micro families, Danfoss publishes two rated output currents per drive:
- Normal Duty is for variable-torque loads (pumps, fans) with around 110% overload capacity.
- High Duty is for constant-torque or high-breakaway loads (conveyors, crushers) with around 160% overload capacity.
On the FC 301/302 T5 380-500 V class these genuinely differ at the same kW. The decoder reads both straight from the design-guide row:
| FC 302 power code (T5) | kW / HP | Normal Duty | High Duty |
|---|---|---|---|
| P15K | 15 kW / 20 HP | 27 A | 43.2 A |
| P37K | 37 kW / 50 HP | 65 A | 97.5 A |
| P75K | 75 kW / 100 HP | 130 A | 195 A |
Size the motor full-load amps against the duty your load actually runs. The AQUA family also exposes the High-Overload column, where a power code such as P30K can map to a lower kW (22 kW) than the literal 30 the code suggests.
FC 102 HVAC: What Decodes and What Does Not
The FC 102 HVAC family is the honest gap in this decoder. It resolves the motor kW/HP, voltage class, and frame size reliably. It does not give a complete output current:
- The High-Duty current is not captured for FC 102 at all; it renders as 'not captured'.
- The Normal-Duty current is incomplete. It is populated on many of the 200-240 V, 525-600 V and 525-690 V rows but is blank on most of the 380-400 V rows, pending finalization from the FC 102 design guide.
HVAC fan and pump loads are variable-torque (Normal Duty), so the missing High-Duty value is less often the sizing case, but you should still confirm the FC 102 output current directly against the design guide rather than assuming the tool is complete for that family. The other four families (FC 301, FC 302, FC 202, FC 51) carry both Normal-Duty and High-Duty currents.
FC 51 Short Codes and How Invalids Are Handled
The Micro Drive FC 51 is a shorter type code by design: there is no separate phase character (the 2-character class S2/T2/T4 carries the phase), the enclosure is fixed IP20, and the RFI filter is fixed H3. A code like FC-051PK75T4IP20H3BXCXXSXXX is complete, not truncated.
When a code cannot resolve to a real drive, the decoder is explicit rather than fabricating:
- A power code that does not exist at the entered voltage class (for example P75K at the 240 V T2 class) returns a 'Not a cataloged drive' verdict, notes which classes the code does exist at, and suggests the nearest cataloged drive in that family and class.
- A power token that is not a recognized code at all, or an undocumented token at a required position (phase, enclosure), fails the verdict as a structural violation, even if a row could otherwise be reached off the shifted characters.
The point is that the tool never invents a current or kW for a combination Danfoss does not publish.