Test transformers
Test transformers standard execution
EPRO Gallspach GmbH’s testing equipment is custom built to meet individual customer requirements. To provide an overview of the available options, below are some examples we have already implemented.
At EPRO, “standard design” means that the equipment is oil insulated.
The advantages of this exectuion are:
- High dielectric strength:
Oil has a very high dielectric strength, allowing oil insulated transformers to generate extremely high voltages. This is especially important for tests requiring extreme voltage levels. - Effective cooling:
Oil serves not only as an insulating medium but also as a coolant. It efficiently dissipates the heat generated during operation, enabling performance under high loads and extending the transformer’s service life. - Selfhealing properties:
In the event of partial discharges or minor breakdowns, oil can partially restore its insulating properties. This offers a certain level of protection against temporary overvoltages. - Long service life:
Oil insulated transformers have proven their reliability over decades and can achieve a very long service life at proper use. - Cost effectiveness:
In certain voltage and power ranges, oil insulated test transformers can be more cost effective than other insulation technologies.
| Model | Execution | max. secondary voltage | Output power continuous | Output power short term (1hr) | PD level | Appr. weight |
|---|---|---|---|---|---|---|
| HVOT 50/5 | oil insulated | 50 kVA | 5 kVA | 10 kVA | < 1pC | 180 kg |
| HVOT 50/10 | oil insulated | 50 kVA | 10 kVA | 20 kVA | < 1pC | 180 kg |
| HVOT 50/20 | oil insulated | 50 kVA | 20 kVA | 40 kVA | < 1pC | 450 kg |
| HVOT 100/5 | oil insulated | 100 kVA | 5 kVA | 10 kVA | < 1pC | 220 kg |
| HVOT 100/10 | oil insulated | 100 kVA | 10 kVA | 20 kVA | < 1pC | 220 kg |
| HVOT 100/20 | oil insulated | 100 kVA | 20 kVA | 40 kVA | < 1pC | 480 kg |
| HVOT 100/50 | oil insulated | 100 kVA | 50 kVA | 100 kVA | < 1pC | 1050 kg |
| HVOT 150/20 | oil insulated | 150 kVA | 20 kVA | 40 kVA | < 1pC | 560 kg |
| HVOT 250/25 | oil insulated | 250 kVA | 25 kVA | 50 kVA | < 2pC | 700 kg |
Most of our test transformers in standard execution also can be equipped with a measurement winding of 100V. This measurement winding allows a quite accurate measurement of the high voltage directly on the transformer. This measurement winding execution is limited in its accuracy on the no load use of the transformer but it is used in this way by several customers.
As already mentioned above, the classical measurement winding execution can lead to quite big measurement errors depending on the load of the transformer and is, out of this reason, not possible to be used in any application case.
We in EPRO Gallspach GmbH have seen this problem and have developed a new execution of measurement winding. This new development guarantees a correct high voltage measurement over the full load range of the transformer. No matter if inductive or capacitive loads occur and even at very high THD current as they are normal in applied voltage tests, the new developed EPRO measurement winding is measuring the high voltage always accurately.