Table of Contents
Advertisement
5.6 Pressure Vacuum Gauge
The pressure vacuum gauge (Fig. 8) indicates whether the head space pressure inside the tank is positive,
negative or neutral. Thepressure insidethe tankwill vary depending onthe load of theunit, temperature of
the oil and ambient temperature outside. As the oil temperature rises, the pressure inside the tank also rises.
Asthetemperaturefalls,thepressurefalls.Itiscommonforatransformertohaveeitherapositivepressure
or a negative pressure.
Do not be alarmed by a consistent negative pressure (for example, if it's winter time
In Wisconsin, it will probably be negative for the duration of the season). However, if the gauge consistently
reads zero and does not appear to be changing with environmental or load conditions, this may be an
indication of a leak and may need attention. Visually inspect the unit for any signs of a leak or damaged seal.
The pressure/vacuum gauge can also be equipped with SPDT alarm contacts (by adding a separate pressure
alarm switch) for remote monitoring of positive and negative pressures. When requested, the
pressure/vacuumgaugecanalsobeequippedwithableederorregulator;whenusedinconjunctionwithan
externalnitrogensupply,positivepressurecanbemaintainedinsidethetank (2.5to 3.0PSI)Theregulatoris
also equipped with a fitting and valve to take gas samples.
No.4 Business Building-2707, China Central Place
Chaoyang District, Beijing-100021, China
北 京 大 林 绿 源 环 保 科 技 有 限 公 司
BEIJING DAELIM GREEN EP TECH CO., LTD.
Fig. 8
Email:info@daelim-electric.com
Advertisement
Table of Contents
