Cut Sheet

© 2016 Littelfuse Protection Relays & Controls
www.littelfuse.com/
Rev: 1-A-062716
Protection Relays
Current Monitoring Relays and Transducers
www.littelfuse.com/ecsw
ECSW SERIES
Description
The ECSW Series of single-phase, AC window, current sensors
includes adjustable overcurrent and undercurrent trip points.
Detects locked rotor, jam, loss of load, an open heater or
lamp load, a broken belt, or loss of suction. LED’s aid in trip
point adjustment and provide fault indication. The built-in
toroidal sensor eliminates the need for an external current
transformer. The output can be electrically latched after a fault,
or automatically reset. Remote resetting of a latched output
by removing input voltage. The unit includes switch selectable
zero current detection and normally de-energized or energized
output operation. Time delays are included to improve operation
and eliminate nuisance tripping.
Features & Benefits
FEATURES BENEFITS
Built-in toroidal
current sensing
Eliminates need to install stand alone
current transformer and provides isolation from
monitored circuit
Encapsulated Protects against shock, vibration, and humidity
LED indication
Visual indication for trip point adjustment and fault
indication
Multiple switch
selectable features
User selectable zero current detection, latched,
normally de-energized, or energized output adds
application flexibility
Adjustable trip delay
Eliminates nuisance tripping and prevents
rapid cycling
Isolated 10A, SPDT
output contacts
Allows control of loads for AC or DC voltages
Operation
When the input voltage is applied, sensing delay on startup
begins and the output transfers (if normally energized is
selected). Upon completion of the startup delay, sensing of
the monitored current begins. As long as current is above
undercurrent trip point and below the overcurrent trip point
(inside the window), the output relay remains in its normal
operating condition and both red LED’s are OFF. The green LED
glows when the output is energized. If current varies outside
the window, the associated red LED glows, and the trip delay
begins. If the current remains outside the window for the full
Wiring Diagram
Current Sensors
L1
N/L2
MC = Motor Contactor
M = Motor
F = Fuses
OL = Overload
RSW = Reset Switch
FSW = Fan or Float Contacts
CR = Control Relay
CS = Current Sensor
MCC = Motor Contactor Coil
V = Voltage
I> = Adjustable Overcurrent
I< = Adjustable Undercurrent
W = Monitored Wire
∆T - Adjustable Trip Delay
Ordering Information
MODEL INPUT VOLTAGE TRIP POINT ADJUST. TRIP DELAY SENSING DELAY ON STARTUP CONNECT.
ECSW3LABT
24VDC
0.5 - 5A 0.150 - 7s 0.1s Terminal blocks
ECSW4HBHT
120VAC
5 - 50A 0.5 - 50s 6s Terminal blocks
ECSW4LADT
120VAC
0.5 - 5A 0.150 - 7s 2s Terminal blocks
ECSW4LBHT
120VAC
0.5 - 5A 0.5 - 50s 6s Terminal blocks
ECSW4MACT
120VAC
2 - 20A 0.150 - 7s 1s Terminal blocks
ECSW4MBHT
120VAC
2 - 20A 0.5 - 50s 6s Terminal blocks
ECSW4MBGT
120VAC
2 - 20A 0.5 - 50s 5s Terminal blocks
ECSW6MBHT
230VAC
2 - 20A 0.5 - 50s 6s Terminal blocks
If you don’t find the part you need, call us for a custom product 800-843-8848