SSAC PLM Series Catalog Page

3 Phase Voltage Monitor

PLM Series
Motor Protector

Description

The PLM Series continuously measures the voltage of each of the three phases. The PLM Series uses a new
microcontroller circuit design that senses Undervoltage, Voltage Unbalance, Phase Loss, and Phase Reversal.
Protection is assured when regenerated voltages are present. Both Delta and Wye systems can be monitored;
no connection to neutral is required.

US Pat #6541954
ANSI Device # 47/27

Protects Against: Phase
Loss, Phase Reversal,
Undervoltage, &
Unbalanced Voltages

8 Pin Plug-in Base

Adjustable Low Voltage
Trip Point

Factory Fixed Unbalance
and Trip Delay

Line Voltages 200...480 V AC,
in 3 Ranges

SPDT Isolated 10 A Relay
Contacts

ASME A17.1 rule 210.6

NEMA MG1 14:30, 14:35
IEEE C62.41-1991 Level B

Approvals:

Accessories

Panel mount kit
P/N: BZ1

Operation

The output relay is energized and the LED glows green
when all voltages are acceptable and the phase
sequence is correct. Under and unbalanced voltages
must be sensed for a continuous trip delay period
before the relay de-energizes. Reset is automatic
upon correction of the fault condition. The output relay
will not energize if a fault condition is sensed as power
is applied. The LED flashes red during the trip delay,
then glows red when the output de-energizes. The
LED flashes green/red if phase reversal is sensed.

Connection

2 Amp

Fast Acting

Fuses

are

Recommended

For Safety

(Not

Required)

Field Adjustment:

Set voltage adjustment knob at the desired
operating line voltage for the equipment. This
adjustment automatically sets the undervoltage
trip point. Apply power. If the PLM fails to
energize, (LED glows red) check wiring of all 3
phases, voltage, and phase sequence. If phase
sequence is incorrect, the LED flashes green/
red. To correct this, swap any two line voltage
connections at the mounting socket. No further
adjustment should be required.

Octal
8 pin socket
P/N: OT08PC

3-phase fuse
block/disconnect
P/N: P0700-241
2 AMP fuse
P/N: P0600-11

DIN rail P/Ns:

C103PM (Al)
017322005 (Steel)

See accessory pages for
specifications.

Relay contacts are isolated.
Dashed lines are internal connections.

F = Fuses NO = Normally Open
NC = Normally Closed

Ordering Table

PLM

Series

Example P/N: PLM6405, PLM9410

X

Line Voltage Voltage Unbalance (Fixed) Trip Delay (Fixed)

–6 - 240 V AC
–8 - 380 V AC
–9 - 480 V AC

X

–Specify: 4, 5, 6, 7, or 8%

X

–Specify from 2 ... 20 s in
1 s increments
(Insert 0 before 1 ... 9)

PLM02B01 02.10.05

Low Voltage Products & Systems7.16

3 Phase Voltage Monitor

PLM Series
Motor Protector

Technical Data

Line Voltage

Type 3 phase Delta or Wye with no connection to neutral
Operating Voltage: Model Adj. Line Voltage Range Line Voltage Max.

240 200 ... 240 V AC 270 V AC

380 360 ... 430 V AC 480 V AC

480 400 ... 480 V AC 530 V AC

Line Frequency 50 ... 100 Hz
Phase Sequence ABC
Power Consumption ≅ 2W for 240 V units

Low Voltage and Voltage Unbalance

Type Voltage detection with delayed trip & automatic reset
Low Voltage: Trip Voltage 88 ... 92% of adjusted line voltage

Reset Voltage Plus 3% of trip voltage

Voltage Unbalance: Trip Unbalance Factory fixed from 4 ... 8%

Reset on Balance -0.7% unbalance typical

Trip Delay: Range Factory fixed from 2 ... 20 s

Tolerance +/-15%

Phase Reversal and Phase Loss

Response Time -- Phase Reversal ≤ 200 ms
Phase Loss ≤ 200 ms
Phase Loss
Reset Automatic

Output

Type Electromechanical relay
Form Isolated single pole double throw (SPDT)
Rating 10 A resistive at 240 V AC, 277 V AC Max.

Life Mechanical -- 1 x 10

Protection

Surge IEEE C62.41-1991 Level B
Isolation Voltage ≥ 2500 V RMS input to output

Mechanical

Mounting* 8 pin plug-in socket rated 600 V AC
Package 3.2 x 2.39 x 1.78 in. (81.3 x 60.7 x 45.2 mm)

Environmental

Operating Temperature -40°C ... +60°C
Storage Temperature -40°C ... +85°C
Weight ≅ 4.4 oz (125 g)

≅ 3W for 380 ... 480 V units

>

35% unbalance

1/2 Hp at 240 V AC; 1/4 Hp at 120 V AC

7

; Electrical --1 x 10

5

*CAUTION: Select an octal socket rated
for 600 V AC operation.

Mechanical View

PLM02B01 02.10.05

Inches (Millimeters)

Low Voltage Products & Systems 7.17