Sutron Corporation 8310 & 7310 Users Manual 8800-1125Rev. 2.7 (BETA) 4/16/2014 pg. 205
Figure 12 - Location of COM1-3 Configuration Jumpers
Figure 13- Comport Configuration Jumper Settings
8310-N Protection/Termination Module Jumpers
Even pins in above figure
against PCB
COM4 Pin 9 configuration - Default is RI
V position
(see figure below)
V position for measuring voltages on AN1
or 4-20mA with 100 ohms switched in
only during measurement.
I position connects precision 100 ohm
resistor from input to ground at all times.