Parker ACR8020, Hardware Manual, Page: 23 / 55

Chapter 2, ACR8020 Motherboard Hardware Set-Up 15
ACR8020 MOTHERBOARD JUMPERS
Digital Input Reference Select (JP17 and JP18)
This jumper selects the reference voltage to be used for the optically-isolated inputs. The
reference voltage selected applies to all inputs; there are no combinations available.
Isolated voltage (VEXT) refers to +24VDC
WARNING
Wiring VEXT with the incorrect voltage will permanently
damage the Digital I/O circuitry. The isolated voltage
(VEXT) is selected as +24VDC.
Refer to Figure 1 for jumper location.
Digital Input Reference Jumper
Input Type Reference Voltage JP17 JP18 User Supplies
Sinking Reference Inputs to
+24VDC Isolated Voltage
(VEXT)
1-2 1-2 Path to GEXT
Sourcing Reference Inputs to
Isolated Common (GEXT)
2-3 2-3 Path to VEXT
Table 2.3 ACR8020 Digital Input Reference Jumper