DESCRIPTION: The Allen-Bradley 825-P is a motor relay used as a protective device for three-phase motors.

It has standard protection features such as thermal overload (thermal model, PTC (positive temperature coefficient), overheat, undercurrent (load loss),

current unbalance and phase loss, overcurrent (load seizure), short circuit, ground fault (residual), ground fault (zero sequence), motor start/run and frequency. This unit requires 110-240VAC power input.

About the 825-P

The 825-P is a protective relay for use with three-phase motors. Manufactured by Allen-Bradley, the device is

It provides standard protections such as thermal overload (thermal modeling), PTC (positive temperature coefficient), overheat, undercurrent (load loss), current imbalance, and phase loss.

overcurrent (load seizure), short dcs-sis.com circuit, ground fault (residual), ground fault (zero sequence), motor start/run and frequency.

For motor start/run protection, this motor relay is capable of starting the motor timer via a protection disable during startup, a startup

notch or pointing device, TCU (Thermal Capacity Utilization) start inhibit, anti-reverse spin timer, emergency start, two-speed protection, reduced voltage start (star-delta), and stall switching to protect the motor.

It can be fitted with RTD-based protection via the 825-PR12D RTD RTD scanner, where up to twelve (12) RTDs can be connected and monitored.

The 825-P is also capable of monitoring event summaries that include information such as relay ID, date and time, trip triggers, and current and voltage amplitudes.

It can also monitor the Serialized Event Record (SER) and motor runtime and history of the last reset and start cycle since the last reset.

Emergency start cycles since the last reset can also be monitored by the unit, which also incorporates a full suite of metering functions.

The 825-P can optionally be fitted with an I/O channel consisting of one (1) 4-20 mA analog output, three (3) control inputs and four (4) contact outputs.

Additional communication interfaces can be installed, including adapters for DeviceNet and Modbus protocols.

The 825-P’s relay outputs also have a 4kV surge strength with a pickup time of < 10ms and provide an insulation voltage rating of 300V AC.

The system has 120V AC/DC (825-PIOD) inputs, a steady state current of 15mA at 2mA and 0.2mA on/off state currents, and on-state and off-state voltages of 15V and 5V respectively.

The system features thermal overload protection and optional voltage-based protection (overvoltage, reactive power, phase inversion, and undervoltage).

The 825-P has a modular construction with a built-in fixed keypad on the front panel and an LCD status display with LED status indicators.

It uses DeviceNet communication options at 125. 250. or 500kbps over distances of 500m, 200m, or 100m and is enclosed in a NEMA 4 (IP65) rated enclosure.

It has an operating temperature of -4 to +140 degrees Fahrenheit, a non-condensing relative humidity of 5% to 95%, and a storage temperature of -40 to +185 degrees Fahrenheit.

It weighs approximately 6.46 kilograms (including power supply and converter modules) and is CE, UL, and CSA listed.