The gear of dry-type transformers (referred to as “tap power switches”) can be divided into two types: “on load” and “off load”. The on load tap power switch can be powered on and adjusted with load, and is all electrically controlled. When controlling, simply press the adjustment button (up and down) to proceed; Most of the small and medium-sized dry-type transformers are equipped with no-load tap power switches. When controlling, it is necessary to turn off the power and open the tap power switch cover on the dry-type transformer itself. Rotate the adjustment lever to the desired car gear, and then accurately measure the resistance of the three-phase winding of the dry-type transformer. The resistance value is basically balanced (generally not exceeding 2%), and then cover the cover tightly and close the switch.

Three car gears for dry-type transformers: first gear: 10500V, second gear: 10000V, third gear: 9500V

First gear: Turn the power switch to first gear, and when the high voltage is 10500V, the low voltage will output 400V.

Second gear: Turn the power switch to second gear, and when the high voltage is 10000V, the low voltage will output 400V.

Third gear: Turn the power switch to third gear, and when the high voltage is 9500V, the low voltage is exported at 400V.

Adjust the tap power switch based on the secondary bus phase voltage. When the secondary working voltage is slightly lower and increases, adjust it by adding 1 to the original car gear (if it was originally in gear II, it should be adjusted to gear III). Conversely, the opposite is true.

1: The voltage regulation method of no-load transformer dry-type transformer: no-load transformer power switch. The transformer should be powered off for operation, and after adjustment, a digital multimeter should be used to check the resistance measurement to confirm that the car gear can be closed when the touch is good.

Generally, dry-type transformers can only change the tap changer under power-off conditions, and cannot change the tap changer position with load. For this type of dry-type transformer, it is necessary to choose a tap changer in advance to ensure that the operating voltage deviation does not exceed the allowable range under high and low loads.

2: There are two types of on load dry-type transformers: one is an on load dry-type transformer with its own transformer coil; Another type is an on load dry-type transformer with a rechargeable AC voltage regulator. The voltage regulating winding of a dry-type transformer with a transformer coil on load includes a tap changer conversion device, which can convert tap changers according to the conversion device when there is a load.