(a) Apply 28VDC to terminals X1 and X2; X1 is positive, X2 is negative.
(b) Check continuity across terminals A1 and A2; B1 and B2, and C1 and C2. The multimeter must show
that contacts are closed.
(c) Remove power. Multimeter must show that contacts are closed.
(2) Relay K4.
(a) Apply 28VDC to terminals 2 and 9; 2 is positive, 9 is negative.
(b) Check continuity across terminals, 1 and 3; 5 and 11; and 10 and 8.
(c) Read Multimeter. It should indicate that terminals 1 and 3,5 and 6, and 10 and 7 are open. Terminals
1 and 4, 5 and 11, and 10 and 8 are closed.
(d) Remove 28 VDC power. Multimeter should indicate that terminals 1 and 4,5 and 6, and 10 and 7 are
closed and that terminals 1 and 3, 5 and 11, and 10 and 8 are open.
(3) Time delay relay K1.
(a) Connect multimeter to terminals 2 and 3.
(b) Apply 28DVC to terminals 2 and 5; Terminal 1 is positive, 5 is negative. Multimeter must show
continuity across terminals 1 and 3 within 30 ± 3 seconds of applying voltage.
(4) Phase sequence relay K5.
(a) This relay will energize only when all three phases are in proper sequence and when input voltage
and frequency are within 10%. of that specified (208 volt, 60 hertz).
(b) Check that power connections are properly connected and that input power is within 10% of that
(c) Replace suspected bad phase sequence relay.
(1) Tag and disconnect the wires to the relay.
(2) See figure 4-27 and remove the attaching hardware.
(3) Pull relay from junction box.
(1) Mount relay using hardware indicated on figure 4-27.
(2) See figure 4-5 wiring diagram and tags and connect leads. Remove the tags. if relay has solder
connections be sure to protect solder joints with heat shrink or equal insulation tubing.
(3) Carefully slide the junction box into place and secure with seven screws and lock washers.
(5) Install the top front cover.
(6) Connect power at power source.