Qualitrol 930 Rapid Pressure Rise Relays (RPRR)

Complies with UPDATED NERC-PRC-005-6 Standard Enforced as of January 1, 2016

Multi-function, electronic pressure monitor with adjustable pressure sensitive sensors that provide rapid pressure rise detection combined with seal-in relay functionality and static pressure monitoring and control. Features continuous outputs for integration with SCADA systems and remote monitoring. Optional multi-sensor models provide logic based operation to eliminate nuisance trip alarm potential.


  • Field adjustable fast pressure rise and slow pressure settings
  • User selectable contacts for momentary or seal-in actuation with front panel LEDs status indicators
  • Constant milliamp output proportional to tank pressure for remote indication or for use with SCADA systems
  • 3 transducer versions available with various logic schemes for greater flexibility and reliable trip functionality
  • Detection and protection of dangerous pressure conditions
  • Electronic pressure sensors continuously output current pressure level with logic to detect dangerous rapid pressure and static (slow) pressure change events
  • Local LED indication and relay actuation for rapid pressure and static pressure events
  • Selectable seal-in relay function keeps the indicating LEDs lit and relays (contacts) actuated until manually reset
  • Eliminate nuisance operations with adjustable sensitivity and multi-sensor logic
  • Special models feature 2 of 3 logic to trigger a trip signal only if 2 of the 3 pressure sensors experience a pressure event exceeding set points
  • Adjustable fast (rapid) pressure rise and slow pressure rise set points for custom operation for your particular acceptable risk level
  • Momentary or seal-in actuation of control and alarm signals can be selected
  • Sensors feature individual set points to for control schemes to provide alarms prior to trip signals should a pressure event occur (to alert personnel of nonstandard conditions without tripping the unit)
  • Monitor pressure remotely with SCADA outputs
  • Continuous 0-1mA or 4-20 mA output signal is supplied from each channel for remote transformer pressure indication or SCADA system integration
  • Up to 9 SPDT relays (6 for fast pressure rise, 2 for slow pressure rise, 1 for power status)
  • Easy to install with retrofit mounting plates and options for many applications
  • Pressure sensors can be mounting via flange mount adapter for retrofit to exiting installations of Qualitrol 900/910 flange mount rapid pressure rise relays
  • Sensors have 1/4″ NPT male fitting for easy mounting or adapting to existing fill ports
  • Sensor are suitable for installation in gas or oil space of transformers
  • Universal power supply accepts any input voltage in the range of 85-265 VAC 50/60 Hz or 110-370 VDC


  • Heavy duty transducers for high humidity applications
  • Weather proof enclosure for mounting outside the control cabinet
  • Single sensor or multi-sensor logic
  • Qualitrol 900/910 retrofit mounting plate
  • SCADA outputs (0-1 or 4-20mA

Group Created with Sketch. Applications

For use on transformer and load tap changer tanks to sense dangerous fast or slow (static) pressure increases and provide alarm and trip functions.