Direct answer: To replace an old elevator drive, send the supplier the complete operating picture, not just a power rating: the traction or door motor nameplate (power, voltage, current, frequency, pole count and motor type), the encoder type and signal format, the control system and its interface, the building type and rated load, the old drive model and clear photos, and the site conditions. A quotation based on the old drive kW alone is a guess — and it is the most common reason a replacement arrives with the wrong current rating, the wrong encoder interface or the wrong control wiring.
Why kW Alone Cannot Size a Replacement
Two drives with the same kW can have different rated currents, different supply branches and different control requirements. A 7.5 kW motor on a 220V branch does not draw the same current as a 7.5 kW motor on a 380V branch, and a closed-loop drive needs encoder feedback that an open-loop drive does not. The 11LIFT elevator inverter product page states the same rule for its own selection checklist: a dependable quotation requires the complete operating profile, not only nominal power. That checklist is the basis for the tables below.
If you are still deciding whether the drive itself is the problem, start with Elevator Drive Modernization: 7 Signs Your Lift VFD Is Due for an Upgrade, which lists the symptoms — jerky rides, leveling errors, noise and obsolete parts — that point to a drive replacement rather than a repair.
The Information Checklist
| Information to send | Why the supplier needs it | Where to find it |
|---|---|---|
| Motor nameplate: power, voltage, current, frequency, pole count, motor type | Sets the drive current rating and supply branch | Motor nameplate in the machine room |
| Encoder type, signal format and resolution | Decides open-loop vs closed-loop and the PG card required | Encoder label and old drive parameter list |
| Old drive brand, model and rated current | Confirms what is being replaced and what wiring exists | Old drive rating plate and manual |
| Control system type, interface, I/O count and protocol | Confirms the new drive can talk to the existing controller | Controller documentation and panel wiring |
| Building type, rated speed, load, travel height, floor count and duty cycle | Checks the drive against the real operating profile | Building and lift specification |
| Brake coil, braking resistor, UPS rescue supply and safety-chain arrangement | Avoids missing rescue and braking functions | Panel and brake documentation |
| Site temperature, altitude, cable length, quantity and destination | Checks derating, cable sizing and export configuration | Site survey |
| Clear photos: nameplate, old drive, encoder, control panel and wiring | Resolves labels that are worn, painted over or in another language | Machine room and shaft head, with power isolated |
Verified 11LIFT Currents: Read the Nameplate, Then Match the Row
The table below uses only manual-verified 380V values published for the 11LIFT range (2.2–37 kW, open-loop and closed-loop versions, 220V / 380V). Use it to check whether a proposed replacement is in the right current class — but do not use it to invent a rating for a model the manual does not list. For 18.5–37 kW on the 380V branch, and for 3.7–7.5 kW on the 220V branch, the product page states that the exact model must be confirmed, so those rows are marked “Confirm” below.
| 11LIFT model (380V branch) | Input current | Output current |
|---|---|---|
| 2.2 kW | 6.5 A | 5.1 A |
| 3.7 kW | 10.5 A | 9.0 A |
| 5.5 kW | 14.8 A | 13.0 A |
| 7.5 kW | 20.5 A | 18.0 A |
| 11 kW | 29.0 A | 27.0 A |
| 15 kW | 36.0 A | 33.0 A |
| 18.5–37 kW | Confirm | Confirm |
Two control facts from the same manual help the supplier choose between versions. Open-loop SVC control gives 180% startup torque at 0.5 Hz with a 1:100 speed range and ±0.5% speed stability, while closed-loop FVC control gives 200% startup torque at 0 Hz with a 1:1000 speed range and ±0.05% speed stability. Closed-loop operation also requires a PG card, which the product page lists as required and priced separately — so state the encoder type explicitly, or the quotation cannot include the right card. For the cost difference that follows from that choice, see Why Does a Closed-Loop Drive Cost More Than Open-Loop?, and for the full open-loop vs closed-loop decision, see Elevator Retrofit: Should You Choose Open-Loop or Closed-Loop?.
How to Collect the Replacement Data: Step by Step
- Photograph the motor nameplate first. Record power, voltage, current, frequency, pole count and motor type, and photograph the plate so worn characters can be checked later.
- Photograph the old drive rating plate. Record brand, model, supply voltage and rated current, and note any fault history or repeated trips.
- Identify the encoder. Record the encoder type, signal format and resolution, and photograph the encoder label. If no encoder is fitted, say so explicitly — that decides open-loop vs closed-loop.
- Record the control system. Note the controller type, the interface and I/O count, the communication protocol and whether the panel will be kept or replaced.
- Record the building and load profile. Note building type, rated speed, rated load, travel height, floor count and duty cycle, plus brake coil, braking resistor, UPS rescue supply and safety-chain arrangement.
- Record site conditions and quantities. Note temperature, altitude, cable length, how many drives are needed and the destination.
- Send photos with the data. Include the nameplate, old drive, encoder, control panel and wiring, taken with power isolated and under safe access conditions.
- Ask the supplier to confirm the match in writing. Before ordering, confirm the proposed model, current class, encoder and PG card, control interface and braking/rescue arrangement against the data you sent.
After the drive arrives, the next step is commissioning, not just wiring it in. How Is a Closed-Loop Elevator Drive Commissioned? covers the checks that follow installation. The Z3300 / D3300 elevator inverter platform is the alternative family to compare when the replacement is a closed-loop drive: D3300 covers 2.2–45 kW at 380–480V, with encoder feedback and a PG card, 200% startup torque at 0 Hz under FVC and 48V battery emergency evacuation. Installation and commissioning must be completed by qualified electrical personnel, following the manual and local rules.
Frequently Asked Questions
Is reporting only the old drive kW enough for a quotation?
No — this is the trap. kW alone does not give the supplier the rated current, the supply branch, the encoder type or the control interface. Two drives of the same kW can need different replacements, and a quotation from kW alone is an estimate that may not fit the motor, the encoder or the controller. Send the full checklist above.
Are photos alone enough?
No. Photos resolve worn labels and confirm wiring, but they do not replace the numbers: motor current, encoder resolution, control protocol and load profile still need to be written down. Send both — the written data and the photos that back it up.
What if the motor nameplate is missing or unreadable?
Record everything else — old drive model and current, encoder type, control system and building load — and tell the supplier the nameplate is missing. The supplier can then advise what further measurement or identification is needed, rather than guessing a rating. Do not estimate the motor power from the old drive kW.
Do I need an encoder for a replacement drive?
Only for closed-loop operation. Open-loop SVC control runs without encoder feedback, while closed-loop FVC control needs an encoder and a PG card. If the old lift ran closed-loop, the replacement must match the encoder type and signal format; if it ran open-loop, say so, so the supplier does not add a PG card you do not need.
Can the old controller stay with a new drive?
Sometimes, but only if the interface, I/O count and communication protocol are compatible. That is why the control system type and interface are on the checklist. A drive that fits the motor but cannot talk to the controller is not a complete replacement.
What should I confirm before ordering?
Confirm the proposed model and current class against the 11LIFT table above (or the equivalent table for the chosen family), the encoder and PG card, the control interface, and the braking and UPS rescue arrangement. A short written confirmation at this stage prevents the most common cause of a second site visit.
Replacing an old elevator drive? Send IDEEI the motor nameplate, encoder type, control system, building load and old drive photos, and contact us for a matched selection. Pricing is provided on inquiry.