MiCOM P139 Relay: Sheet and Feeder Settings

Short answer

The MiCOM P139 is a protection and bay control relay for medium- and high-voltage feeders. It combines overcurrent, directional, reclosing, breaker failure and control of up to six switching devices, with four setting groups and about 300 predefined bay types.

What the P139 is

The MiCOM P139 is the feeder management and bay control unit from Schneider Electric (MiCOM line). It joins overcurrent protection and bay control in one case, for medium-voltage bays or high-voltage bays with basic topology. It protects cables, lines, transformers and motors in networks with isolated neutral, resonant earthing, impedance earthing or solid earthing. See also Easergy P5 relay.

Protection and control functions

Function	ANSI	Note
Definite-time overcurrent, four stages	50/51	Includes negative sequence
Inverse-time overcurrent, two stages	51	Includes negative sequence
Short-circuit direction	67	Depends on version
Switch onto fault	50
Reclosing	79	Three-phase
Synchronism check	25	Optional
Earth-fault direction (steady-state and transient)	67W/YN	Transient, optional
Motor protection and thermal overload	37/48/49/50S/66
Negative sequence (unbalance)	46
Voltage and frequency	27/59/47/81	Depends on version
Directional power	32	Depends on version
Breaker failure	50BF
Programmable and interlocking logic	—

The exact availability of each function depends on the relay version (the manual covers several part numbers). Functions can be enabled or disabled one by one; unused ones are hidden from the menu, which simplifies the settings.

Bay control

The relay governs up to six switching devices with status indication, with up to 20 binary inputs for positions and up to 12 output relays. Before issuing a command, the interlocking logic checks that the new state is allowed by the bay and station topology; if not, it rejects the command and raises an alarm. A predefined bay type (about 300) assigns inputs, outputs and interlocks in one step. This is complemented by how the MiCOM P139 binary inputs are tested.

How the settings are organized

P139 settings are split in two levels:

Configuration parameters: which functions exist, how inputs and outputs are assigned, communications and bay type.
Function parameters: the values of each protection, organized in four independent setting groups, plus global and control parameters.

A good order is to start from the bay type, assign inputs and outputs per the terminal diagram, and only then load the protection values from the coordination study. Parameters can be changed from the local panel or from the PC interface with the manufacturer’s software.

Communications and measurements

The P139 carries two information interfaces, IRIG-B synchronization, and, as options, the InterMiCOM protection interface and IEC 61850. Besides the electrical measurements, it can include a 20 mA input, 20 mA outputs and inputs for resistance thermometers.

How we help

We configure MiCOM relays remotely: bay type, inputs and outputs, protections and communications, with a backup before and after. See remote configuration for Easergy and MiCOM relays.

References

Schneider Electric, MiCOM P139 feeder management and bay control, technical manual P139/ES M/Aa8, volumes 1 and 2.

Frequently asked questions

What is a MiCOM P139 relay?

A feeder management and bay control unit from Schneider Electric: it protects against short circuits, earth faults and overloads and controls the bay's switching devices.

How many setting groups does the P139 have?

Four independent protection setting groups, to adapt the relay to different network operating conditions.

What does the bay type do in the P139?

Selecting it automatically assigns the inputs, outputs and interlocking logic of that bay topology. About 300 are predefined and user models can be loaded.