UNI-T UT305A, User Manual, Page: 18 / 26

18
Testing Enclosed Relays
1. Press SET and then press / to set emissivity to
relatively low for uninsulated connectors or relatively
high for plastic encased relays or for bakelite enclosed
relays or insulated connectors.
2. Press
YELLOW button to select MAX.
3. Start to scan.
4. Measure the relay casing, looking for hot spots.
5. Measure electrical connections on relay terminals
looking for hot spots.
Testing Fuses and Buss Connections
1. Press SET and then press / to set emissivity to
relatively high for paper covered fuse body or insulated
connections.
2. Press
YELLOW button to select MAX.
3. Scan the paper covered length of fuse.
4. Without releasing the trigger, scan each fuse. Unequal
temperatures between fuses may indicate voltage
or amperage imbalance.
5. Press
SET and then press / to set emissivity to
relatively low, for metal fuses and caps and insulated
buss connections.
6. Press YELLOW button to select MAX.
7. Scan each end cap on each fuse/
Note
Unequal temperatures or a high temperature indicates
loose or corroded connection through the fuse buss
spring clip.
Testing Electrical Connections
1. Press SET and then press / to set emissivity to
relatively low for uninsulated connectors or buss
connections or relatively high for insulated connections.
Note
Conductors are typically smaller than the Thermometer’s
spot size. If the spot size is bigger than the connector,
the temperature reading is the average within the spot.
2. Scan the conductor, moving toward direction of
electrical connector (quick connect, wire nut, buss
connection, or lug).