A closed-loop elevator drive is commissioned only when the encoder, the PG card and the drive agree on speed and position at every stage: at standstill, during acceleration, at full speed and at the landing. If any one of those checks is skipped, the lift may run, level once, and still fail under a different load or direction.
Before power-up: what must already be true
Confirm the drive model and PG card type against the motor encoder before the first run. The 11LIFT closed-loop elevator inverter covers 2.2-37kW and supports both open-loop and closed-loop configurations, so the control mode itself must be set deliberately, not left at a default. Record the motor nameplate, encoder type and PG card type on the commissioning sheet: every later fault diagnosis starts from that record. For the choice behind closed-loop in the first place, see Open-Loop vs Closed-Loop Elevator Drives: How to Choose and Why Does a Closed-Loop Drive Cost More Than Open-Loop?.
How to commission a closed-loop elevator drive: the checklist
- Isolate, inspect and identify. With the lift isolated and locked out, inspect motor cables, encoder cable routing and shielding. Encoder cables must be kept away from power cables and shielded as the manual requires; a noisy encoder signal looks exactly like a tuning fault.
- Check encoder wiring and mechanical fitting. Verify each encoder conductor against the PG card terminal diagram, check the connector is fully seated and locked, and confirm the encoder is rigidly coupled with no slip. A loose coupling passes a no-load test and fails under load.
- Fit and set the PG card. Confirm the card matches the encoder type: incremental ABZ, SIN/COS for synchronous motors, or absolute encoder types. Set the card and drive parameters for that encoder before any rotation test.
- Enter motor data and select the control mode. Enter nameplate power, voltage, current and speed, then select closed-loop vector control. Do not copy parameters from a different motor or a different lift.
- Run the encoder direction and autotune checks. Run the drive at low speed and confirm the reported speed and direction match the actual motor rotation. Correct direction before increasing speed; reversed feedback is a fault, not a tuning preference.
- Test zero-speed holding. With the brake released under controlled test conditions and the car empty, confirm the drive holds the car at zero speed without drift or rollback. Repeat the test with a load change where the site procedure allows, because holding torque is the point of closed-loop control.
- Test levelling in both directions. Run the car to landings in both directions, empty and loaded where permitted, and record the stopping position at each landing. Adjust levelling parameters only one step at a time and retest after each change.
- Test start, stop and re-levelling. Check for smooth starts, controlled stops and stable re-levelling when the load changes at a landing. Jerks, hunting or repeated re-levelling attempts are commissioning findings, not passenger complaints to be left for later.
- Record, label and hand over. Record final parameters, PG card type, encoder type and test results, label the PG card and encoder cable, and leave the commissioning sheet with the building maintenance file.
Verified 11LIFT control values to use
| Control mode | Starting torque | Speed control range | Speed control accuracy |
|---|---|---|---|
| SVC (sensorless vector control) | 0.5 Hz, 180% | 1:100 | ±0.5% |
| FVC (closed-loop vector control) | 0 Hz, 200% | 1:1000 | ±0.05% |
Use these values as the reference for what closed-loop control is designed to deliver: full torque at zero speed and a much wider, more accurate speed range than sensorless control. They do not replace the manual for the specific model fitted, and they do not justify skipping the zero-speed or levelling tests above.
Sign-off table: pass, fail or retest
| Check | Pass looks like | If it fails, do this first |
|---|---|---|
| Encoder wiring and PG card match | Terminals, card type and encoder type all agree on the sheet | Stop and correct the card or wiring; do not tune around a mismatch |
| Direction and speed feedback | Reported speed and direction match actual rotation | Correct feedback wiring or direction setting, then retest at low speed |
| Zero-speed hold | No drift or rollback at standstill | Recheck encoder coupling, PG card setup and holding parameters |
| Levelling accuracy | Consistent stopping position in both directions and under load change | Adjust one parameter at a time and retest; check encoder alignment |
The Z3300 and D3300 elevator inverter platform (2.2-45kW) shows why the record matters: an open-loop and a closed-loop drive can look similar on a quotation, but their commissioning sheets, PG card requirements and test results are different documents.
Frequently asked questions
Can commissioning be done from the drive keypad alone?
No. The keypad sets parameters, but encoder alignment, zero-speed holding and levelling can only be verified by observing the motor and the car. A parameter list is not a commissioning record.
What if the lift levels correctly once?
One good stop is not a pass. Repeat the test in both directions and under a load change, because encoder slip, feedback noise and tuning errors often appear only on the second or third run.
Can I skip the zero-speed hold test if the brake holds the car?
No, and this is the trap. The brake is a safety and parking device, not proof that the drive controls torque at zero speed. If the drive cannot hold at zero speed, the car can move when the brake releases, even though it stood still before.
Should I use SVC values when commissioning in FVC mode?
No. Use the values for the mode actually selected: SVC is 0.5 Hz at 180%, 1:100 and ±0.5%, while FVC is 0 Hz at 200%, 1:1000 and ±0.05%. Mixing the two sets hides a mode error.
When should commissioning stop and support be called?
Stop when the same fault returns after wiring, card type and direction have all been verified, or when any test requires bypassing a safety function. Record the fault, the parameters and the test conditions before calling support.
A signed commissioning sheet should name the drive, the encoder, the PG card, the control mode and the result of every test above. Without that sheet, the next engineer is starting again.