HD7500 SERIES

On-line purification device for transformer on-load tap changer insulation oil

Nowadays. Most of the large transformers have installed the OLTC to insure the voltage quality of electric system and customers in the power industry. But the frequent switches of OLTC with load have produced a great mount of dissociated carbon, water and other indigents. The deterioration of oil will decrease the oil insulation, limit the switching times of OLTC and even endanger the safety of the transformers.

The HTC7500series equipment is mainly used in the bypass circulation, filtering system of OLTC. It can timely filter the oil while the transformer operates normally, or it can automatically filter the oil after the switching of the OLTC. The equipment can efficiently discord the impurities like dissociated carbon, water and oxides in the filtering cycles to ensure the quality of oil. Thus it can guarantee the oil insulation, increase the switching times, postpone the repairing period, decrease the power cut times, assure the voltage quality and improve the safety and reliability of the OLTC.

The HTC7500 series equipment is usually install near the OLTC permanently as a special facility. There are all kinds of influx and accessories with different functions to b choose.

Technical parameters

Functions and effects

Wipe off dissociated carbon in oil

Wipe off water in the oil

Improve the electrical medium intensity

Postpone the repairing period

Increase the switching times

Postpone the insulation oil life

Decrease power cut times

Ensure the power quality

Characteristics

All climate box of Stainless steel.

Standard control box of Stainless steel.

Remote control system, demonstration of operation state and filtering core.

Positive and negative direction control of the motor, protection of over-load of motor start and phase-lacking.

Three oil valves to the oil chamber of OLTC.

Cabinet fans (according the location)

Heater to prevent condensation.

Humidity relay, ranging from 50%~100%

Clock

Notes

Automatically run the filtering equipment once after the operation of OLTC, the operating time can be set according the requirement from 0 to 99 hours, but it is usually set as 30minutes. Another way is to filter everyday at the fixedtimelasting2 hours. The two methods can be chosen accordingly.

When the equipment is set in wet tropic or sub-tropic areas, the temperature of the machine box and filter is usually lower than dewdrop. Heater should be chosen to prevent the machine box from condensating so that water could not enter and the machine could work normally.

The orifice of the machine box is used to keep ventilation.

Installation style: hanging or side fixed.

Applicable to types of OLTC:V,NS, M, T,F,G model

Selection of filtrating core

Filtrating elements is the filtration unit installed in the filtrating casing, the filtrating elements available for HTC7500 series can as following:

The element for removing the impurity of dissociate carbon

The element of adsorbing water and oxide

The type of element for removing particles is : HC7500SKZ8H

The type of element for dewatering is: HC7500SWT8H

Filtrating accuracy: ≤1μm

Filtrating ration:β≥1000

Selection of size

H7500-07 flux 7L/min

H7500-10 flux 10L/min

H7500-12 flux 12L/min

Standard collocation:

Bypass valve built in the filtering casing H7500 and difference pressure signaling equipment

Built in overflow valve pump

Display of filtering element status and alarm indicator

Control relay EASY 412-AC-RC

Fully enclosed oil pump, AC, three phase 380V