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.
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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||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|
|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|
|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.
GENERAL ISO10656 INTEGRATED TRANSGUN RESISTANCE WELDING TRANSFORMER DRAWING
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