If you are going to replace a GAMAK electric motor whose nameplate shows IE3, that marking is one of the pieces of information that helps you identify your motor; whether a new motor fits your machine is decided by frame, shaft, mounting, power and speed. This article explains how to read the IE information and the GAMAK series code on the plate, which dimensions to use to check technical suitability, and what should be sent to DRG MOTOR.

Grey three-phase electric motor with DRG MOTOR logo – technical suitability check when replacing an IE3-labelled motor

What does the IE3 marking on the plate identify?

The IE class is a marking that states the motor's efficiency class according to IEC 60034-30-1; the GAMAK catalogue also refers to this standard. If you see IE3 on your plate, note it as one of the motor's identification details. Include this information in your replacement request, but do not treat it as a selection criterion on its own. Two motors carrying the same IE marking does not mean their feet, shaft or speed are the same.

If your site has a specification, project condition or regulatory requirement regarding efficiency class, state it clearly in your request; the assessment is made taking that requirement into account. This article only helps you identify the nameplate of your existing motor; it does not compare the efficiency of a new motor.

Reading GAMAK IE3 series codes

Three series appear in the IE3 tables of the GAMAK catalogue:

  • AGM3EL: listed under aluminium frame; the catalogue gives aluminium frames in the 63–250 range and states that 71–250 frames use bolt-on feet.
  • GM3EL / GM3E: listed under cast iron frame; 132–450 frame range, with feet cast together with the housing. Four- and two-pole tables start at 5.5 kW (132S).
  • C.AGM3EL / C.GM3EL: compact series; in the catalogue examples the same power is given in one frame size lower. For example, in the catalogue C.AGM3EL 160 H 2d is 22 kW, whereas in the standard series a 22 kW two-pole motor is in the 180M frame.

According to the coding structure the catalogue explains for its Ex-proof motors, the rest of the type code contains the frame height, a length letter, the number of poles and a package length letter; type names in the standard series are written in the same order (for example AGM3EL 132 S 4a). If you see "C." at the beginning of the code, your motor is from the compact series and may have a smaller frame than a standard motor of the same power. This distinction is easily overlooked in a replacement.

Technical suitability: beyond the IE marking

The main checks that determine whether a new motor fits the existing location and machine:

  • Frame and shaft: IEC frame code, shaft diameter × length and key. The GAMAK catalogue gives its dimension tables to IEC 60072-1; the existing motor's dimensions should still be verified on site.
  • Mounting: B3 foot, B5 or B14 flange, B35 foot and flange. Foot hole spacing and flange dimensions are compared.
  • Power and rated speed: kW and actual nameplate speed on the plate; not to be confused with speed class (1500, 3000).
  • Voltage, frequency and connection: the performance tables in the GAMAK catalogue are given for 3-phase 400 V 50 Hz; take what is written on your plate as the reference. Whether the motor suits the existing supply must be determined by checking the nameplate voltage, frequency, manufacturer tolerances and connection arrangement together. The relationship with the panel and starting arrangement should be assessed by competent technical staff.
  • Application: type of machine, starting load, start-stop frequency, use of a drive and environment.

The compact series example clearly shows that the same kW value alone does not indicate suitability. A similar distinction exists on the DRG side: DRG-132S-4 and the compact DRG-112M-4K are both 5.5 kW with a nameplate speed of 1460 rpm, but the first has a 132S frame and a 38×80 mm shaft, the second a 112M frame and a 28×60 mm shaft. Foot holes also differ (A 216 mm versus 190 mm). You can use the technical drawings page to compare dimensions.

Send DRG MOTOR the nameplate photo, type code and connection dimensions of your existing motor; add any specification requirement too, so that the option is assessed together with technical data and operating conditions.

Examples of DRG models that can be assessed

DRG Motor is a manufacturer, supplier and seller of electric motors. The models below, from the three-phase asynchronous motors in the electric motor shop, were chosen to show different frame situations; suitability is checked with dimension and application data:

  • DRG-132S-4 (aluminium): 5.5 kW, rated 1460 rpm, 132S, 38×80 mm shaft, 10.7 A at 400 V.
  • DRG-112M-4K (aluminium, compact): 5.5 kW, rated 1460 rpm, 112M, 28×60 mm shaft.
  • DRG-180M-4 (cast iron): 18.5 kW, rated 1470 rpm, 180M, 48×110 mm shaft, 33.5 A at 400 V.

DRG models are specified with IP55, class F insulation and IC411 cooling for −15…+40 °C ambient and altitudes up to 1000 m. In the DRG MOTOR online shop, models up to 3 kW are listed as 230/400 V and models of 4 kW and above as 400/690 V; any special voltage or different frequency requirement should be stated separately. Mounting is B3, B5 or B35; B14 dimensions are confirmed with the order. For other powers see the general purpose electric motors page.

Questions about replacing an IE3-labelled motor

My plate shows IE3; does the new motor have to be in the same class?

That depends on your site's specification and the requirements it is subject to. If there is such a condition, state it in your request. Technical suitability, however, must be checked with dimensions, power, speed and application data regardless of IE class.

My code starts with C.AGM3EL; what does this change?

"C." indicates the compact series. In the catalogue, the compact series delivers the same power in one frame size lower. So in a replacement, frame height, shaft and foot dimensions may differ from the standard series; dimensions should be checked on site.

Does the difference between AGM and GM affect the replacement?

In the catalogue tables, AGM is listed under aluminium and GM under cast iron frame. Connection dimensions may be similar for the same frame code; however, the choice of frame material should be assessed according to weight, foot design and ambient conditions.

The plate is worn and I cannot see the IE information; is that a problem?

What is really needed for a technical assessment is power, speed, voltage and dimensions. If these can be measured on site, a review is possible. If an IE class is required by specification, state that separately.

Information needed for the assessment

  • A sharp nameplate photo and the full type code (including the C., AGM or GM prefix)
  • IE class and duty type information written on the plate
  • kW, rated speed, voltage, frequency and current
  • Frame code, mounting, shaft diameter × length and key
  • A, B, C, H for foot motors; flange outer diameter, hole circle and spigot diameter for flange motors
  • Any specification or project requirement regarding efficiency class
  • Driven machine, starting condition, use of a drive and ambient conditions

You can send this information via WhatsApp or info@drgmotor.com, call +90 (542) 666 11 11 or use the contact page. If you add the models you want assessed to the quote list and share them with your nameplate and dimension data, the review is made according to your conditions.

See current prices of DRG MOTOR electric motors and order online in our storeSEE PRICES →

Technical Sources

  • GAMAK — Technical Catalogue (Turkish edition) — Standards and recommendations: IEC 60072-1, IEC 60034-30-1 — printed page 18.
  • GAMAK — Technical Catalogue (Turkish edition) — Electrical design: IEC 60034-30-1:2014 efficiency classes — printed page 40.
  • GAMAK — Technical Catalogue (Turkish edition) — 3-phase standard asynchronous motors: frame material (aluminium 63–250, cast iron 132–450), removable and cast-on feet — printed page 68.
  • GAMAK — Technical Catalogue (Turkish edition) — 3-phase standard asynchronous motors: aluminium frame IE3 tables (3-phase 400 V 50 Hz; AGM3EL 180 M 2a) — printed page 69.
  • GAMAK — Technical Catalogue (Turkish edition) — 3-phase standard asynchronous motors: cast iron frame IE3 tables (GM3EL; 2- and 4-pole tables starting at 5.5 kW 132 S) — printed pages 76–77.
  • GAMAK — Technical Catalogue (Turkish edition) — 3-phase compact asynchronous motors: C.AGM3EL and C.GM3EL tables (C.AGM3EL 160 H 2d) — printed pages 85–86.
  • GAMAK — Technical Catalogue (Turkish edition) — Ex-proof motors: nameplate coding structure (C = compact) — printed page 105.