MPS100
3
FUNCTIONAL DESCRIPTION
CURRENT INPUTS
The relay monitors three phase and ground currents
individually. The ground current can be obtained from
a ground sensor (doughnut) or residually connected
current transformer. Nominal current input can be 1 or
5 amperes, based on style chart configuration.
THERMISTOR INPUT
MPS100 relays include 1 Thermistor input. The ther-
mistor may be either positive temperature coefficient
(PTC) or negative temperature coefficient (NTC),
0.1Ω-30KΩ.
CONTACT INPUTS
2 Contact inputs are provided for connection of
external protective devices or for remote reset.
OUTPUTS
All MPS relays include 4 form C output relays. Each
relay can be programmed to operate on a combination
of protection functions.
Function ANSI Code When Active Range
Max. Start Time 48 Starting 1-250 Seconds
Too Many Starts 66 Starting 1-10 starts within 1-60 minute period
Undercurrent Level 1 37 Running 10-90% full load, 1-60 seconds
Undercurrent Level 2 37 Running 10-90% full load, 1-60 seconds
Load Increase 51L Running 60-150% full load, 5 seconds
Overcurrent Level 1 - Stall 51R Running 100-500% full load, 0.5-10 seconds
Overcurrent Level 2 - Short 50 Always 400-1200% full load, 0.0-0.4 second
Thermal Level 1 49/51 Always 50-99% of Thermal Capacity
Thermal Level 2 49/51 Always 100% of Thermal Capacity
Unbalance Level 1 46 Always 50% of Unbalance Level 1, 1 second
Unbalance Level 2 46 Always 10-40% full load, 20-120 seconds
Phase Sequence 47 Starting n/a
Ground Fault Level 1 50G Always 1-100% of full load, 1-60 seconds
Ground Fault Level 2 50N Always 1-100% of full load, 0.0-2.0 seconds
Comm. Port Failure 3 Always 3 consecutive parity/CRC errors
Internal Relay Failure 3 Always n/a - Relay Self Test
External Fault 1 86 or 94 Always n/a - External Contact
External Fault 2 86 or 94 Always n/a - External Contact
Thermistor Level 1 49R Always 100 - 30kΩ, 2 seconds
Thermistor Level 2 49R Always 100 - 30kΩ, 2 seconds
Unstable Current --- Always 10% max. of full load, 1% min. of full load
Table 2 - MPS Protective Functions
HUMAN MACHINE INTERFACE (HMI)
The Human Machine Interface (HMI) includes a backlit
2-line LCD display and a keypad to allow local interac-
tion with the relay. Likewise, all measured, calculated
and recorded data can be accessed. Three (3) LEDs
are also included to indicate the status of the relay and
the associated equipment.
REMOTE COMMUNICATIONS
The relay includes an RS485 communications port
which can be used for communications with a remote
computer. The communications link enables monitor-
ing of the settings and available data.
GRAPHICAL USER INTERFACE (GUI)
A personal computer based program is available for
interaction with MPS relays. This provides logical,
screen-based, program for relay setup.
SELF TESTS
MPS relays include extensive self test capabilities. This
includes power-up tests, manual tests and continuous
(background) tests. Any self test failure is reported as
an Internal Failure, which can be configured as an
alarm or trip condition.
