Spectrum Controls 1746sc-OAP8I - Manual (Page 24)

Installation Instructions
Isolated-Circuit
Discrete Input and Output Modules
22
On the 1746sc-OAP8I, each status
indicator (0–7) illuminates when the
processor commands the module to turn
on the corresponding output. The
indicators do not necessarily indicate the
presence or absence of AC power at an
output. The Blown-Fuse indicator
illuminates when any 1 of the 8 output
fuses blows.
Checking For Blown Fuses (1746sc-OAP8I only)
If a fuse blows on the 1746sc-OAP8I, the following occurs:
1. The blown-fuse LED indicator illuminates (provided your module is
receiving power from the chassis).
2. The module indicates to the logic controller’s input image table which
fuse has blown. This allows for fuse monitoring and smart power-down
sequencing of equipment after a circuit failure.
You can verify that a fuse has opened by visually checking the fuses, shown
below. Turn all power off, and replace blown fuses with the specified re-
placement part only. Substitutes are not acceptable.
OAP8I
F8
F7
F6
F5
F4
F3
F2
F1
Replaceable Fuses (F1–F8)
3 A, 250 V, 2 AG SLO-BLO
Littelfuse part 229003
ISOLATED TRIAC 120/240 VAC
OUTPUT
STATUS
FUSE
1746sc-OAP8I