CEE Relays Ltd

Tel:   +44 1753 576477    Fax: +44 1753 825661
NP900 Series of relays
NP900 relay
The NP900 series is a significant improvement over the NP800 series. This new series includes many advanced features such as IEC 61850 communication protocol as standard, a large graphical display, wider measurement ranges and fully customisable logic functions. 
NP900 relays are programmed using the new SMARTline (Setting, Measurement, Analysis, Recording, Time-saving) configuration software which also includes SMARTsoft for NP800s, Railway and Regulation. 
This series is ideal for the protection of all types of Generation, 
Industrial, Railway, Transmission and Distribution networks.
Click on the links below to download the individual brochures (in PDF format), or the link at the bottom to download the General Brochure for the whole series.
Common characteristics for the NP900 series: 
• Comprehensive protection IEDs for feeders, transformers, generators, motors or busbars 
• Network control, alarm, measurement and monitoring IEDs 
• IEC 61850 protocol (PRP, HSR) 
• IEEE 1588 time synchronisation (PTP) 
• Customisable HMI (measurement display, control, MIMIC) 
• PLC (programmable logic functions)
• Power measurements have an IEC 62053-22 accuracy class of 0.5 (Except for the NPP915, which has an accuracy class  of 0.2S)

Some products in the NP900 series are available with an integrated arc detection option for exceptionally fast tripping during arcing faults. The relevant products in the list below are highlighted with the Arc Detection logo.
Arc detection logo
Feeder protection relays
Feeder protection relay with overcurrent and earth-fault functions.
PDF, 2.0Mb
Advanced feeder protection relay with directional and non-directional overcurrent, earth-fault, undervoltage and overvoltage functions.
PDF, 2.0Mb
Machine protection relays
Motor protection relay, adaptable to two-speed motors or those with soft starters or star/delta starters.  Includes overcurrent, earth-fault, locked rotor and thermal overload protection.
PDF, 2.0Mb
Advanced motor protection relay incorporating all of the functions of the NPM910 with additional voltage, frequency and power protection.
PDF, 2.0Mb
Advanced generator protection relay including vector-shift and rate-of-change-of-frequency protection.
PDF, 2.0Mb
Transformer protection relays
Transformer protection relay for transformers; may also be used for differential protection of motors and generators.
PDF, 2.0Mb
Transformer voltage regulation relay incorporating current and voltage protection and a manual or automatic AVR.
PDF, 2.0Mb
Bus-bar protection relays
Voltage and frequency relay for protecting bus-bars.  Includes a feature to check synchronisation across switchgear prior to closing.  Ideal for load shedding applications.
PDF, 2.0Mb
Control, Measurement and Monitoring relays
Signalling relay.  Uses digital inputs and outputs in complex logic functions and may be used to extend the I/O capability of other NP900 relays.
PDF, 2.0Mb
Network Control relay. Measures electrical quantities (voltage, current, frequency etc.) and provides trip circuit supervision, synchronisation checks and automatic re-closing of circuit breakers.
PDF, 2.0Mb
Power monitoring IED.  Measures electrical quantities with a high degree of accuracy; recommended as a network monitoring device where protection functions are not needed. 
PDF, 2.0Mb
Energy management IED with a built-in fault-locator.  This product will record overcurrent, earth fault and over- and under-voltage situations but will not initiate a trip. 
PDF, 2.0Mb
For a general overview of NP900 relays, download the 
PDF, 4.1Mb
For more information on the integrated arc detection system used by the NP900 relays, click here.