The SCR19 Series Power
Controllers are designed to
proportion electric power to resistive
loads only, such as ovens, furnaces,
heat sealers, etc. (NOTE: They are
not designed to drive transformers or
any inductive load.) The controllers
consist of power semi-conductors
(SCRs), properly-sized heat sinks,
trigger circuitry, and fuses supplied
on panels for surface mounting.
The power controller accepts a
4 to 20 mA dc output from a
temperature controller or can be
supplied with manual option using
a remote potentiometer.
The SCR19 Series controllers offers
two methods of proportional control –
Zero-voltage-switched and
Phase-angled-fired. With the
Zero-voltage-switching mode, the
controller switches on complete
cycles of the ac supply voltage. The
trigger circuit is designed to turn on
the SCRs as close as possible to the
point where the AC sine wave
crosses through zero. In effect, the
line voltage
is turned on and off and applied to
the heaters in whole cycles. With an
input of 4 to 20 mA, the output will be
off below 4 mA and full on at 20 mA.
Proportioning action is obtained by
varying the number of cycles on to
the number of cycles off. The output
will vary from one cycle on and nine
cycles off at low input, to all cycles
on at maximum input. This output is
integrated by the heaters which
produce a smoothly proportioning
heat output that varies directly with
the input signal. With the
Phase-angle-fired mode, the power
to the load is controlled by governing
the point of turn on (firing) of each
half cycle of the full AC sine wave.
† All dollar amounts on this site are shown in US currency.
Note: Comes with complete operator’s manual Ordering Example: (1) SCR19Z-24-040 SCR, Zero-Voltage-Switching, 240V, 40A, $300.00
Part Number Builder
Option Descriptions
(1)
Single or 3 Phase
Select 1 for Single Phase 3 for 3 Phase
(2)
Method
Select Z for Zero-Voltage Switching P for Phase-Angle Firing
(3)
Voltage
Select -12 for 120 Vac for single phase only -20 for 208 Vac for phase angle firing single phase only -24 for 240 Vac -48 for 480 Vac
(4)
Current
Select -040 for 40 Amps -060 for 60 Amps -080 for 80 Amps
(5)
Phase-Angle Firing Items
Select for Zero-Voltage Switching leave field blank -S9 for the STANDARD Soft start 9 seconds -S15 for Soft start 15 seconds -S30 for Soft start 30 seconds -S60 for Soft start 60 seconds -S120 for Soft start 120 seconds -V for Voltage limit
NOTE: All combinations may not be valid, check spec sheet for valid part numbers.
