CACSW Integrated Power Factor Capacitor AC Switch0 pages

Cognito Quam
Industrial Electronics, Control, Robotics and Automation

CACSW Integrated Power Factor Capacitor AC Switch
The CACSW connects a three- or single-phase, 25 A power factor capacitor bank to the line, employing
bypassed, zero crossing, solid state thyristor switches. Its phase fault detector can be used to either monitor
the line for phase integrity or the capacitor bank circuit for fuse state as well as line faults.
Control input and
"Ready" output
terminals

Phase fault monitor
input terminals

Operation DIP switch
(next to the control input
terminals)

Power On LED shows
power supply status and
flashes when phase fault is
detected

Enabled ON LED shows
switch activation and
flashes when the thyristors
are overheated, typically
due to bypass relay failure

Control supply
terminals
Phase U output
terminals

Phase S line
input terminals

Phase R line input
terminals

Phase V output
terminals

DIN rail latch
The CACSW PF capacitor AC switch

The CACSW solid state thyristor switches connect to the capacitor bank at zero voltage difference without
any disturbing inrush currents. They are then bypassed by a relay to eliminate all thyristor conduction losses
and are protected against overheating, typically caused by failure of the relay contacts. The control input is
digitally filtered to reject noise and the unit responds within a maximum time of 2.5 seconds.

Line connection
Own control supply
Overheat protected
solid state relays
Zero crossing type
solid state relays
Switch bypass relay
Sampling time
Phase fault detector
Stand-alone or slave
operation
Forced state
Indicating LEDs
Isolated control
circuit
Protection
DIN rail enclosure
Removable terminals

CACSW Feature Summary
Powered independently, no connection to the neutral is required.
Powered separately at the control supply terminals.
Solid state relays circuits switch the 25 A compensating capacitors in and out of
the line at every sampling instant.
Each capacitor is switched in when the line voltage equals the capacitor voltage
thus eliminating capacitor inrush current and extending capacitor service life.
Bypass relay across each solid state switch minimizes/eliminates switch losses.
Minimum 1 second sampling time gives a maximum 2.5 s response time.
The switch is monitored for phase faults and/or blown fuses.
DIP switch selectable slave mode allows stand-alone or external master control.
DIP switch forced state turns the switch on regardless of control input state.
LEDs show the power supply state ("PWR", green) and the switch activation
status ("ENBL", yellow). The "PWR" LED flashes on a detected phase fault (or
blown fuse) while the "ENBL" flashes on thyristor switch overheating.
Control circuit is galvanically isolated enhancing safety and noise immunity.
Against line overvoltages, faults and power circuit overheating.
Versatile DIN rail mountable plastic box.
Removable terminal blocks ensure quick and neat wiring installation.

r.2 Mar13 Copyright © 2012-2013. Cognito Quam Ltd, PO Box 67212, Melissia, Athens 15102, Greece.
Tel/fax: +30.210.8049475 - http://www.cognitoquam.gr
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