CEE Relays Ltd

Tel:   +44 1753 576477    Fax: +44 1753 825661
Static Relays
WTGA relay
"Static" Relays are electronic relays which use integrated circuits without microprocessors.  They typically perform only one protection function.

CEE's range of single-function relays are highly reliable and many have remained in service for decades without incident.  The relays listed here are all still available to purchase and make ideal spare and replacement parts for older transmission and distribution networks.  Some of these relays may be used as substitutes for obsolete items; see the link below.
Relays in this series use a modular plug-in base design ("R-case") in one of four standard widths. They may be individually or rack-mounted.

Selected versions of these relays are Nuclear Certified class E1 and are in use in both old and new nuclear installations.  Contact us for more details. 
Are you looking to replace an old relay but can't find it on this list?  Our guide to Obsolete relays will help you select the closest equivalent from our other products. 
General Protection Relays
Three-phase differential protection for rotating machines
PDF, 0.6Mb
Biased three-phase differential protection for transformers
PDF, 0.9Mb
Overfluxing protection for power transformers
PDF, 0.5Mb
Out-of-step protection for synchronous motors
PDF, 0.7Mb
Frequency protection relay
PDF, 0.7Mb
High impedance differential protection
PDF, 1.0Mb
Direct Current Earth-fault protection
PDF, 0.1Mb
Directional Overcurrent relay (Brochure includes ITD7112, which is now obsolete)
PDF, 1.5Mb
LV zero-sequence / earth fault current protection
PDF, 1.3Mb
The ITG range of Instantaneous or Definite Time overcurrent relays.
For sensitive earth fault / neutral overcurrent see the ITH7111 / ITG7111, below.
Only one relay in this range offers undercurrent protection (ITG7118)
PDF, 0.9Mb
IDMT overcurrent relays in the ITG range, each designed to operate on a specific IDMT curve.
The ITG7xx5 and ITG7xx6 relays are updated versions of the ITG7xx1, 7xx2, 7xx3 and 7xx4 relays and have a wider range of current settings. 
PDF, 0.9Mb
Sensitive earth fault relay.  Brochure also includes the ITG7111 neutral overcurrent relay, which is less sensitive (also the ITG7011 which is now obsolete).
PDF, 1.4Mb
Alternator negative sequence protection
PDF, 1.6Mb
The ITV range of Voltage Restrained Overcurrent relays
PDF, 1.5Mb
Underpower (PTG7111) or overpower (PTG7113) relays using nominal line voltages
PDF, 1.1Mb
The STEP range of temperature supervision relays with 4 or 6 RTD inputs
PDF, 2.3Mb
Synchronisation check relay
PDF, 0.6Mb
Rotor earth fault relays for synchronous machines
PDF, 0.7Mb
The TTG range of phase over- and under-voltage relays, instantaneous or definite time, for AC applications
PDF, 0.7Mb
Instantaneous (TTG7034) or definite time (TTG7134) neutral voltage displacement relays
PDF, 0.7Mb
Voltage balance relay
PDF, 0.5Mb
TTGD7112
Time-delayed positive sequence overvoltage. Included in TTG7000 brochure, above.  Please note that the instantaneous version TTGD7012 is no longer available.
Automatic re-closer for distribution networks.  Please note that models TTR7116 / TTR7126 / TTR7136 are no longer available.  The TTR7146 has one rapid cycle and three slow cycles to re-close a circuit breaker.
PDF, 2.6Mb
TTRT7136
Automatic re-closer, similar to the TTR7146 but with three independently adjustable cycle times: rapid, intermediate and slow.  No brochure is available at this time.
Active- or Reactive-underpower, reverse power or overpower relays using Wattmeters
PDF, 0.9Mb
Alternator loss-of-field relay
PDF, 0.7Mb
Protection Relays for Direct Current Systems
The TTB range of over- and under-voltage relays for DC applications. 
PDF, 0.9Mb
Auxiliary Relays
Auxiliary relays are available for performing lock-out, timing and other logical functions.  While they do not perform measuring or protective functions they may be combined with protection relays to make your power system protection more versatile. Details of auxiliary relays are provided here.