Rice Lake Static Weighing - Manual (Page 13)

Installation 9
2.7.2 Digital I/O
The Digital I/O can be configured as either digital inputs or digital outputs as determined by the DIO menu (see
Section 3.4.4 on page 29). The inputs are active (on) with low voltage (0 VDC) and can be driven by TTL or 5V
logic without additional hardware. Use the DIG I/O menu (see Section 3.4.4 on page 29) to configure the digital
inputs. LEDs on the CPU board light when digital inputs are active (see Figure 2-4).
Digital outputs are typically used to control relays that drive other equipment. Outputs are designed to sink not
source, switching current. Each output is a CMOS circuit, capable of sinking 24 mA when active. Digital outputs
are wired to switch relays when the digital output is active (low, 0 VDC) with reference to 5 VDC supply. LEDs on
the CPU board light up when the digital outputs are active (see Figure 2-4).
Screw Screw
Screws
Screw DIO LEDs
Figure 2-4. Digital I/O lights and screw locations
Table 2-4. J4 Pin Assignments (Digital I/0)
Connector Pin Signal
J4 1 +5V
2 Ground
3 DIG I/O 1
4 DIG I/0 2
5 DIG I/O 3
6 DIG I/O 4
2.8 Enclosure Reassembly
Once the cabling is complete, position the backplate over the enclosure and reinstall the screws. Use the torque
pattern shown in Figure 2-1 on page 6 to prevent distortion. Torque to 15 in/lbs (1.7 N-m).
2.9 Board Removal
If you must remove the CW-90/CW-90X CPU board, use the following procedure:
1. Disconnect power to the indicator. Remove backplate as described in Section 2.4 on page 7.
2. Disconnect power supply cable from connector J9 on the CW-90/CW-90X CPU board.
3. Disconnect the wires at the following connectors: J1, J2, J3, J4.
4. There are two boards: the CPU board and the keypad display board. Remove the five screws connecting
the CPU board (see Figure 2-4), then lift the board out of the enclosure.
To replace the CPU board, reverse the above procedure. Be sure to reinstall cable ties to secure all cables inside the
indicator enclosure.