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Integrated transgun resistance welding transformers 50Hz and 60 Hz

Low price welding transformers, particularly integrated 'transgun' resistance welding transformers for water-cooled robot welding guns, manual welding guns and welding machines. These ISO standard 50Hz or 60Hz resistance welding transformers have been tested by independent test laboratories and meet the requirements laid down by ISO/TC 44/SC6 in ISO10656:1996, ISO5826:1999 and related international standards. They range from 25 kVA to 103 kVA, delivering short circuit currents of up to 67kA at voltages of up to 13.5 V and are available for most supply voltages, normal production being 400V. A photograph of a set of ISO10656 welding transformers is shown below.

Due to their small physical size and high output characteristics, integrated transgun resistance welding transformers also have uses in special machine applications. The direct coupling of these welding transformers can reduce electricity consumption costs as well as costs of installation, due to the reduced kVA demand on the electrical system.

For enquiries for welding transformers: E-mail by clicking including delivery location so we can use an appropriate currency and estimate transport costs.

A new range of Medium Frequency (MF) resistance welding transformers is shown on a separate page MFtransformers.htm

In collaboration with other companies Isomatic has also developed and now manufactures transformers for MIG/MAG (GMA) welding machines. Any small transformer, for welding or otherwise, can be made to order.

This page is also available in Française, Resistance welding transformers France  Deutsch Resistance welding transformers Germany and Español Resistance welding transformers Spain

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Resistance welding transformers

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Design and manufacture of ISO10656 Integrated transgun resistance welding transformers

We perform extensive computer modelling of the electromagnetic phenomena and thermal processes in order to optimise the design for the desired criteria. The iron core consists of C-cores wound from high quality cold rolled grain-oriented (CRGO) electrical steel. Cooling water flows through the secondary winding, made from rectangular copper tube.

All transformers have built in current sensing toroids, with an output of 150mV per kA. Two thermoswitches are fitted, one monitoring primary temperature set at 140 degree C and the other monitoring secondary temperature set at 80 degree C. Primary connection terminal arrangements are common for all sizes from 25kVA to 61kVA. Connection for 76kVA and 103kVA are larger, to permit connection of larger dimension primary cables. Different aluminium alloy connection boxes can be offered, either with direct connection through multi-contact type plugs or cable glands. Special boxes and covers can be manufactured when specified by the customer.

Technical specifications and a generic drawing for ISO10656 transformers are given below. There are two frame sizes, H and J. Transformers rated from 25kVA to 36kVA are produced in the H size. All other transformers are produced in the J size. All J size transformers are interchangeable and all secondary connections on H and J transformers are identical, allowing shunts and bus bars to be standard.

For increased performance go to Turbo Transformers on the Isomatic Lab. site

For BMW style transformers go to BMW T/Fs on the Isomatic Lab. site

Type numbers and specifications from ISO10656 range of integrated transgun resistance welding transformers
Type ITF25 (H size) ITF32 (H size) ITF36 (H size) ITF48 (J size) ITF54 (J size) ITF61 (J size) ITF76 (J size) ITF103 (J size)
Order No 220V - 50/60Hz ITF25220P ITF32220P ITF36220P ITF48220P ITF54220P ITF61220P ITF76220P ITF103220P
380V - 50Hz ITF25380P ITF32380P ITF36380P ITF48380P ITF54380P ITF61380P ITF76380P ITF103380P
400V - 50Hz ITF25400P ITF32400P ITF36400P ITF48400P ITF54400P ITF61400P ITF76400P ITF103400P
415V - 50Hz ITF25415P ITF32415P ITF36415P ITF48415P ITF54415P ITF61415P ITF76415P ITF103415P
440V - 50Hz ITF25440P ITF32440P ITF36440P ITF48440P ITF54440P ITF61440P ITF76440P ITF103440P
500V - 50Hz ITF25500P ITF32500P ITF36500P ITF48500P ITF54500P ITF61500P ITF76500P ITF103500P
Continuous rating Sp [kVA] 17.7 22.5 25.2 34 38 43 53.7 73
Standard 50% Rating S50 [kVA] 25 32 36 48 54 61 76 103
No-load secondary Voltage U20 [V] 4.5 5.6 6.3 6.3 7.1 8.0 10 13.5
Continuous secondary current I2p [kA] 4.0 4.0 4.0 5.4 5.4 5.4 5.4 5.4
Short circuit sec'y current Isc [kA] +/- 10% 33 36 39 45 53 59 63 67
L1 [mm] 238 245 265 258 285 310 370 460
L2 [mm] 224 231 251 244 271 296 356 446
L3 [mm] 170 170 170 190 190 230 260 350
L4 [mm] 70 70 70 90 90 90 90 90
L5 [mm] 106 106 106 125 125 125 125 125
L6 [mm] 150 150 150 160 160 160 160 160
Electrical connection Spacing E [mm] 26 26 26 26 26 26 26 or 45 45
Depth [mm] 8 8 8 8 8 8 8 or 10 10
Screw thread [y] M6 M6 M6 M6 M6 M6 M6 or M8 M8
Mass [kg] 18 21 25 29 31 36 40 55
Colour orange purple blue blue green grey yellow brown
Measuring coil 150 mV/kA +/- 1.5% at 1 kOhm resistance
Primary thermoswitch Cut-off temperature 140 +/- 6 deg.C
Secondary thermoswitch Cut-off temperature 80 +/- 6 deg.C

Isomatic Lab also manufactures other transformers with unique characteristics for special purposes

A general drawing is shown below. Dimensions for the most popular models of resistance welding transformer are given on the individual technical drawings, which can be downloaded in AutoCAD .dwf format and viewed with a free downloadable viewer.

Click on any of the following kVA ratings to view the transformer in a new window and download the relevant drawing.


ISO integrated transgun resistance welding transformer

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