What the 1020 alarm means

The motor thermal model exceeded its limit from sustained over-torque operation; the drive trips to protect the winding. Our engineers run into this alarm every week on EFORT EC2-S controller + TSINO drives controllers, and a single on-site inspection usually identifies the problem.

Most common causes

  • Payload parameter lower than the real tool weight
  • Worn reducer adding drag
  • Brake dragging on the axis
  • Duty cycle too hot with no cooling margin
Field note: In our repair stats the first cause has the highest hit rate, so confirm it first before digging further.

Step-by-step field fix

  1. Set the correct payload and inertia values
  2. Backdrive the axis by hand to feel for mechanical drag
  3. Verify the brake releases cleanly
  4. Reduce speed or add dwell in the hottest program section
  5. Log axis current over a shift to confirm
Safety first: For EFORT 1020, this alarm family involves the DC bus, which sits at several hundred volts and stays charged for minutes after power-off - touching terminals is a shock hazard. The self-serviceable action is Set the correct payload and inertia values; anything past that falls under the DC bus and power stage and needs a certified engineer. On EFORT 1020: checking incoming voltage at the disconnect and looking at breakers and fuses is fine to do yourself; opening the cabinet to touch bus terminals or pulling power modules needs a qualified electrician.

How we diagnose drive alarms on site

EFORT 1020 belongs to the drive & power stage family. On EFORT 1020 the failing stage is matched servo drives assigned per axis in the cabinet on the EFORT robot controller - the fault sits on the energy chain: mains input, rectification, DC bus, braking resistor, inverter power devices and the drive board. We start reading EFORT 1020 at the pendant alarm list (four-digit codes, 1xxx / 3xxx / 4xxx segments).

The chain involved in EFORT 1020 runs: three-phase mains -> rectifier -> DC bus (bus capacitors) -> brake chopper / braking resistor -> inverter (IGBT) -> motor.

When EFORT 1020 fires, the site usually reports Payload parameter lower than the real tool weight first, but the real cause is often cooling: More than half of power-stage alarms are not a dead device but a device cooked by failed cooling. A stopped cabinet fan, a packed filter mat or a dusted air duct keeps IGBT junction temperature high: intermittent over-temperature first, hard fault days later. On these alarms we open the power module and look for cracked thermal paste and felted dust in the duct, then measure phase-to-phase output and insulation to frame. Swapping the module without cleaning the duct just buys the same failure again.

Field notes on this page cover EFORT 1020 (Motor Overload (TSINO)); written by the Henghuan repair team, updated 2026-10-01.

Not sure? Don't force it — contact an engineer

Give us the alarm code, robot model and the action at the moment of the alarm, and our engineers can give you a quick read — phone or video remote diagnosis is free.

Get a Free Remote Diagnosis See Repair Services

Hotline: +86-20-39029800 · WhatsApp: +86-188-1886-2860

Related Drive & Power Stage alarms

1001 — Drive Overcurrent (TSINO Servo) 1010 — Drive DC Bus Overvoltage (TSINO) 1011 — Drive DC Bus Undervoltage (TSINO)
Same family: this code belongs to the Drive & power stage alarms family - the page collects all Drive & power stage-family codes we have handled, with the common inspection order and spares.
Other brands: we also keep field-fix libraries for JAKA · AUBO · ROKAE and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the EFORT 1020 alarm mean?

The motor thermal model exceeded its limit from sustained over-torque operation; the drive trips to protect the winding. Our engineers run into this alarm every week on EFORT EC2-S controller + TSINO drives controllers, and a single on-site inspection usually identifies the problem. EFORT 1020 sits in the drive & power stage family; on our work orders the highest-frequency trigger for this code is "Payload parameter lower than the real tool weight".

QCan I clear a EFORT 1020 alarm myself?

Whether EFORT 1020 clears on its own depends on the outcome of "Set the correct payload and inertia values". Finish the flow with "Log axis current over a shift to confirm" to confirm EFORT 1020 - do not skip it. If that step is clean, the second most frequent cause on EFORT 1020 is "Worn reducer adding drag". When EFORT 1020 keeps coming back it is not a one-off trigger - especially if Log axis current over a shift to confirm is where you get stuck. Do not keep producing through EFORT 1020.

QFor drive/power alarms like EFORT 1020, what spares do you bring on site?

The commonest causes we see on EFORT 1020 are "Payload parameter lower than the real tool weight, Worn reducer adding drag, Brake dragging on the axis", so we stock the van against those. For EFORT 1020 specifically, we stock the van along the energy chain: braking resistors, bus capacitors, input fuses, drive-board supply parts and the common power modules for the brand. For EFORT 1020, drive alarms usually stop the whole line, so they sit at the front of our dispatch queue. Before we roll, tell us what EFORT 1020 shows on the pendant alarm list (four-digit codes, 1xxx / 3xxx / 4xxx segments) and what the machine was doing - phone or video triage is free.

The content on EFORT 1020 was written by Henghuan Robotics service engineers from hands-on repair experience. Alarm descriptions are our own reference summary and may differ by controller or software version — defer to EFORT documentation, or contact us to confirm. Henghuan is an independent service provider with no affiliation or endorsement by EFORT.