Troubleshooting The Output Opto-Isolator; Output Voltage Check; Output Opto-Isolator Pin Location - Emerson Liebert iCOM Training And Service Manual

Troubleshooting the Output Opto-Isolator

The opto-isolator IC chips used in these circuits are the H11J (output) devices. The
drawing shows the pin location for component checks on the output opto. The
indented circle in the upper left hand corner of this chip indicates the location of Pin
1. Note that the number sequence is in a "U" format: downward 1, 2 and 3 on the
left and upward 4, 5 and 6 on the right.

OUTPUT VOLTAGE CHECK

Pin 1 Receives the DC source voltage (3.3 VDC range)
Pin 2 Completes the DC source to the digital ground
Pin 3 No voltage signal at this point
Pin 4 Receives the AC source voltage signal from the input transformer
Pin 5 No voltage signal at this point
Pin 6 Completes the AC voltage path to the gate of the triac (24VAC)
Note that all AC source checks are referenced to the associated transformer
neutral and/or the safety ground, and that the DC source reference is to V- or
digital ground.
An Output Opto-isolator is a DCV device used to control the ACV Triac and load
device.
iCOM
1
2
3

Output Opto-Isolator Pin Location

151
Control Training and Service Manual
6
5
4