Relays. Test for some degree of continuity.
Normal condition shown may
indicate some normal resistance
With no external load applied to
any relay field, test from terminal
1 to 3 for continuity. This tests K2
contact closed through the field of
K4. To test the closed contact of
K1, check for continuity between
terminals 4 and 7. An open circuit
between terminals 3 and 8 tests
between terminals 6 and 10 tests
the open contact of K 1, between
5 and 9 the open contact of K2.
and between 7 and 9 the open
contact of K 1 through the field of
Connect external 24-28 vdc load
to terminals 2 and 3.
that resistance measurements are not made in
circuits that have current flowing in
them. The meter will be seriously
Test from terminals 6 to 5. An open circuit indication
tests the open contact of K3
through the field of K1 and also
test action of relay K3.
terminals and 3. Connect 24-28
vdc loads to terminals 1 and 3.
Test from terminal 3 to 8 for continuity. This tests
both K4 contacts as closed and the action of relay K4.
terminals 1 and 3 and connect it
to terminals 5 and 6. Test from
terminals 4 to 7 for an open circuit
indication. This tests the closed
contact of K3, and the action of
K1. Check between terminals 9
and 7 for continuity to test the
closed contact of K 1 through the
field of K2. Check between
terminals 6 and 10 for continuity.
This tests the closed contact of
Remove Control Terminal Board (Model
Removal. Refer to figure 4-69 and remove
the remote control terminal board.
Figure 4-69. Remote control terminal board, removal and installation (Model MEP-018A).
Change 8 4-80