Johannesburg, South Africa, 25 November 2010 - Three phase motor protection and control applications have been simplified with the introduction of the NewCode motor protection relay which provides comprehensive motor protection with time and date-stamped event and fault records, as well as integrated user configurable control logic functions and standard starter control blocks.
Available from CHI Control, a division of ACTOM, the 7-field inputs and 4-relay outputs are fully configurable with a Profibus DPV 1 communication protocol. The use of a modular GSD file allows the user to select the cyclic data telegram from a single byte in and out to a maximum of 2 bytes out and 6 bytes in. By allowing acyclic data transmission, it caters for the accessing of critical but less frequently required data when the need to access the data arises. The NewCode has been packaged into 45mm wide din rail-mounted housing with separate current sensing modules to suit different motor kW ratings.
Revealing these details, a news release from CHI adds that control panel-mounted LED’s indicate fault conditions as well as the status of the 7-field inputs and 4 output relays, assisting maintenance personnel with visual indication.
It says relay settings and configuration are automatically backed up onto a memory module plugged into the side of the relay on the T Bus expansion slot. This enables the transferring of all relay settings to a backup relay.
The NewCode configuration software is a user friendly environment with logical groupings and useful accessories such as a 3 phase recorder volts, amps and power factor, a spectrum analyser to measure the harmonic content of the phase currents, and a calculator to assist with current and thermal calculations, says CHI. The actual value screen allows the viewing of the voltage, current, power, thermal capacity, status of field inputs and relay outputs as well as displaying the bit values of the PLC input bytes. This enables the monitoring of real time actual values and status on one screen.
The release goes on to say that the test screen provides a simulation platform. It can be used by the system integrator or the commissioning staff to functionally test the NewCode relay or to train personnel. By entering typical plant operation values a typical what-if scenario is created. Relay behaviour and performance can be evaluated by watching input signals, status conditions and relay outputs.
It adds that the simulator will trigger the event and fault recording as would occur in real time. To distinguish between real events and simulated events the event and fault record will have a “Sim” entry in the first byte of the record where-as the real event or fault will have an “Act” in the first byte. This is to prevent the use of the simulator to fabricate an apparently true event or fault record as well as to identify when the simulator may have been used to test a condition or generate a trip to test the relay trip circuit.
CHI points out that protection features include: thermal overload class 3 to class 40 with full thermal memory to IEC 60255-8; locked rotor vectorial stall; unbalanced current; single phasing; undercurrent or load loss; run-stall or jam; starts per hour; over/under frequency; voltage phase rotation; under-voltage; over-voltage protection; insulation failure; earth leakage and earth fault.
Control is facilitated by timers, counters, logic truth tables, latches, a real time clock, a pulse generator and comparators.