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Electronic Winding Temperature Indicator

Accurate Controls are approved suppliers, installers and commissioners of Ashridge Engineering Limited transformer electronic monitoring equipment.

Standard Features

  • 3-wire PT100 input
  • One Winding CT input (0-10A)
  • System conditioning monitoring and alarm
  • Pump controller monitoring (852-116)
  • Fan controller monitoring (852-116)
  • Auto cooler exercising (852-116)
  • Wide range power supply (42-265V)
  • One, two or three gradients

Ancillary Equipment

  • Standard or custom PT100 designs
  • One Winding CT input (0-10A)
  • Standard or custom thermowells/pockets
  • CT's for Pumps and Fans monitoring
  • Remote monitoring via GPRS or SMS
  • Remote alarm via GPRS or SMS



Installation by Accurate Controls

  • Accurate Controls install all Ashridge 852 electronic
    winding temperature instruments in accordance with
    Ashridge’s recommended installation instructions.
  • We use an armoured screened cable to connect to the
    Pt100 probe and all the other cables connected to the
    instruments are with screened 2.5mm² cables
  • All of the screen earths are taken to a single
    star point earth
  • By following the above we minimise the potential
    effects of EMC upon the Ashridge instruments.
  • As a result we have the confidence to offer a 5 year
    warranty with any Ashridge instrument supplied and
    installed by Accurate Controls.


Model descriptions

  • 852Plus National Grid approved model featuring watchdog + 5 relays, 2 analogue outputs, Modbus communications, intelligent cooling system, expired life and data logging. The 852Plus is a single winding version with single display.
  • 852-112 Entry level WTI, featuring watchdog + 2 relays, 2 analogue outputs, Modbus and DNP3 communications, expired life and data logging. The 852-112 is a single winding version with dual display.
  • 852-113 Featuring watchdog + 3 relays, 2 analogue outputs, Modbus and DNP3 communications, expired life and data logging. The 852-113 is a single winding version with dual display.
  • 852-116 This model features watchdog + 6 relays, 2 analogue outputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-116 is a single winding version with dual display.
  • 852-118 Featuring watchdog + 8 relays, 4 analogue outputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-118 is a single winding version with dual display.
  • 852-216 This model features watchdog + 6 relays, 2 analogue outputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-216 is a 2 winding version with dual display.
  • 852-218 Featuring watchdog + 8 relays, 4 analogue outputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-218 is a 2 winding version with dual display.
  • 852-318 This model features watchdog + 8 relays, 4 analogue outputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-318 is a 3 winding version with dual display.
  • 852-338 Top of the range, this model features watchdog + 8 relays, 4 analogue outputs, bottom oil and ambient (or tap changer) PT100 inputs, Modbus and DNP3 communications, intelligent cooling system, expired life and data logging. The 852-338 is a 3 winding version with dual display.
  • 852-013 Ashridges Oil Temperature Indicator, featuring watchdog + 3 relays, 1 analogue output, Modbus and DNP3 communications and data logging, with single display.

Spares and Options:


PT100 probe with thermowell/pocket


Miniature measuring CT's

(current transformers)


Recommended armoured/

screened cabling for PT100


Please contactus for further information.