РТ400 current relay

Purpose:

Current relays monitor DC and AC circuits and issue signals to protection or control equipment.

Distinctive features:

The measured RMS current is shown on a three- (four-) digit display.
Operation over a wide range of measured currents. Two output relays with changeover contacts allow control signals to be issued at different levels of the measured current and with different time delays.
Independently programmable pickup thresholds, reset hysteresis, and pickup and reset delays on two independent channels provide both minimum and maximum current and voltage relay functions in a single device.
A choice of tripping curves is available for the current relay.
Password protection against unauthorised reprogramming.
Powered from a DC or AC supply.
Galvanic isolation between the measuring input, the supply input and the output contacts.
Current can be measured over a wide frequency range — from DC to 400 Hz — as can the RMS value of a current of arbitrary waveform within that range.
Data exchange and control via an RS485 interface using the Modbus protocol.

Replacing 132×132 and 172×172 analogue panel instruments with digital panel instruments made by NPP VEL