The 100P phase angle SCR (current version) includes a card that is of surface mount construction.
The control card has a 6-position selector switch (SW1) that allows the user to easily configure the control.
4-20mA, 0-10V & Input Resistance Selection:
The input will accept the standard 4-20madc signal @250ohm impedance or 500-ohm and is switch selectable.
SW1 POS 1 and POS 2 are each a 500-ohm resistor. Close SW1 POS 1 or SW1 POS 2 and the input is 500-ohms. Close SW1 POS 1 and SW1 POS 2 and the input is 250-ohms. SW1 POS 1 and POS 2 open input impedance is 20kΩ impedence for manual potentiometer or 0-10 Vdc control.
You will need to readjust the bias and gain adjustments after input resistance is changed. See question that covers adjustment of bias & gain.
Ramp Speed Adjustment:
Close SW1 POS 3 ramp is 4.5 seconds.
Close SW1 POS 4 ramp is 3.5 seconds.
Close SW1 POS 5 ramp is 2.5 seconds.
Close SW1 POS 6 ramp is 1.5 seconds.
SW1 POS 3 through SW1 POS 6 open ramp is 0.5 seconds.
SW1 POS 3 through SW1 POS 6 closed ramp is approximately 13 seconds.