Surge Pressure Relay Dual Protection For Power Capacitor / Oil Immersed Transformer

Pressure & Surge Pressure Relay for Oil-immersed Transformer
 

Product Overview
 
Pressure & Surge Pressure Relay converts the rate of pressure variation inside the oil tank into an electrical signal, designed to safeguard the oil tanks of equipment such as transformers, power capacitors and reactors. It consists of two integrated components: a surge pressure relay (also known as a pressure gradient relay) and a static oil pressure relay, which take the tank pressure rise rate and static tank oil pressure as their respective measurement sources.
 
When the pressure rise rate inside the oil tank exceeds 3±1 kPa/s, the surge pressure relay actuates in advance and outputs an electrical signal, enabling the system to trigger an alarm while the tank pressure remains at a low level during severe sudden failures. The response time of the surge pressure relay shortens as the pressure rise rate increases. The net pressure increment upon its actuation — calculated as the product of the pressure rise rate and response time — is generally limited to 25 kPa ±20%, ensuring early alarming at low tank pressure under catastrophic fault conditions.
 
If the tank pressure rise rate is lower than 3±1 kPa/s, the surge pressure relay remains in its normal non-actuated state. To guarantee comprehensive tank safety, the unit is equipped with a static oil pressure relay, which sends out an alarm signal once the oil pressure reaches its preset alarming threshold.

Operating Conditions
 
1. Applicable to oil tanks of oil-immersed transformers, power capacitors, reactors and other sealed oil-filled electrical equipment;
2. Ambient temperature range: -45°C to +50°C.