1.15 ELECTRICAL SYSTEM Continued.
a. 208 VAC, Three Phase. When operating off the 10 kW TQG (or other external source), 208 VAC (3-
phase) is applied to connector A9J2 on power panel located on rear, driver's side of LMS. Setting
Power Panel circuit breaker A9CB1 "ON" applies 208 VAC, 3 phase to pin combinations 2 and 4, 6
and 8, and 10 and 12, common side, of POWER MODE selector A4S1-A in Rear Control Panel. When
POWER MODE selector is set to EXT position, 208 VAC, 3 phase is applied across POWER MODE
selector contacts to circuit breaker A4CB9. If A4CB9 is closed ("ON") and relay A4K5, AUX HYD
PUMP relay, is energized, the 208 VAC, 3 phase is applied through cables 1A4W3 and 1A1W2 to the
AUX HYD PUMP motor. The AUX HYD PUMP motor drives the auxiliary hydraulic pump
providing CBPS system hydraulic fluid flow in the ECU when operating CBPS on EXTERNAL
power. Relay A4K5 energizes when POWER MODE selector is positioned to EXT and A4S6, EXT
HYD PUMP switch, on Rear Control Panel is closed ("ON").
b. +24 VDC. The converter (1A4A12) must be turned ON when operating the CBPS using external
TQG power. It converts the 208 VAC, 3-phase input into a +24 VDC output, which is applied to the
24 VDC bus in the Rear Control Panel from connector A12J2 through cable 1A4W10 and A4J10.
+24 VDC from the 24 VDC bus is applied to pin X1 of relay A17K1 coil via the closed contacts of
A4CB3, closed contacts pins B1 and B2 of relay A4K14 in the relay box, and diode A17D1. The
ground connection at pin X2 of relay coil A17K1 is connected to the negative side of the ECV battery
pack through cable 1A4W1. When diode A17D1 conducts, relay A17K1 energizes and 24 VDC is
applied across A17K1 contacts A1 and A2 to the positive side of the ECV battery pack. This keeps
the ECV battery pack charged during CBPS operation using EXTERNAL POWER.
115 VAC, Single Phase. The ECV cannot be started or run while power mode selector switch is set to
EXT which allows external power to operate the CBPS.
115 VAC is tapped off POWER MODE selector A4S1A at pin 3 and applied to the coil (X1 and X2) of
relay A4K14. This energizes relay A4K14, opening its contacts A2 and A3, disabling the ECV fuel
solenoid which prevents anyone from starting the ECV while operating CBPS using EXTERNAL
power. A4S1A pin 3 is also connected to A4S1B pin 21. A4S1B pin 23 is connected to the NEUTRAL
connection from the TQG. When A4S1 is positioned to EXT, 115 VAC is applied through closed
contacts of A4CB10 to the 1A4A10 receptacle circuits. Receptacle Panel operation remains the same
as described in the Power Distribution Internal Power (ECV) paragraph.
The 10 kW TQG will only support heat stage 1 DURING EXTERNAL OPERATION.
Turning on heaters 2 through 4 will shut down the TQG. Under NBC conditions,
Only heat stage 1 may be used when operating the CBPS on EXTERNAL power. The 10KW generator
power output is not sufficient to operate the remaining heat stages while operating CBPS on EXTERNAL
POWER. If the CBPS is operating on INTERNAL POWER (ECV), the 10KW generator output is sufficient
to operate any combination of the first 3 heater stages. When stage 4 heater is used in combination with any
other electrical heater stage a generator with 30KW or higher output is required. The stage 4 heater can be
used with the 10KW generator if it is the only heater stage selected while CBPS is operated using
Heat stage 4 may be used only if a 30KW or larger generator set is used as the external
power source while operating the CBPS on external power.