Solid State Relays
G3NH
201
Replacement
Be sure to turn off the power before replacement.
1. First, remove the four screws (shown below as “A”) and the
transparent protective cover from the relay housing and then
disconnect the wiring.
2. Remove the four screws (shown in the following as “B”) and the
nameplate from the relay housing.
3. Remove the three screws (shown in the following as “C”) from
inside the housing and pull the Base Assembly up to detach. (The
Base Assembly cannot be removed thoroughly because of the
leads connected to the base.)
4. When the Base Assembly is detached, you will see the leads
connected to the built-in thyristor module. Pull the connector to
disconnect the leads. At this point, if any defect exists in any of
the electronic components on the PWB, the SSR may fail again
even after the replacement of the built-in thyristor module. In such
a case, consult OMRON about appropriate remedial action.
5. Remove the two screws (shown in the following as “D”) and take
out the built-in thyristor module.
Assembly of the thyristor module must be performed in the exact
reverse order of the previous disassembly steps 1 to 5.
6. Before mounting the new thyristor module for replacement, wipe
off the silicone grease adhering to the heat sink, keep clean the
jointing surfaces of the heat sink and thyristor module, and apply
the new grease (supplied as an accessory) to the jointing
surfaces. Secure the thyristor module to the heat sink with the two
screws “D” and tighten each screw to a torque of 2.45 to
2.94 N·m.
7. Connect the thyristor module to the PWB with the socket. (The
socket may be inserted in either direction.) Assemble the Base
Assembly with the heat sink by aligning the PWB with the PWB
securing groove and the protective cover with the protective cover
securing groove, respectively, while exercising caution not to get
any of the leads caught between the Base Assembly and the heat
sink.
8. Secure the Base Assembly with the three screws “C”. Because a
large current flows into these screw parts, make sure that any of
the screws is not clogged with foreign matter and tighten each
screw to a torque of 4.41 to 4.90 N·m.
9. Check the assembled parts again for any lead caught between
the Base Assembly and heat sink and for proper fitting of the
PWB and protective cover into their respective securing grooves.
Then, replace the nameplate and secure it with the four screws
“B”.
10.Complete the wiring and secure the protective cover with the four
screws “A”.
11.Apply power to the relay and check the relay for proper operation.
A
A
A
A
B
B
B
B
Name plate
C
Base
Connector
Protection cover
PWB
Connecting to thyristor module
Protection cover
securing groove
D
D
PWB securing groove
Heat sink
