MONITORING SYSTEM OVERVIEW AND DIAGRAMS -- CONTINUED
The transmission gauges operate from system power (+24 -- 28 V dc) supplied from the master relay through the
15--amp circuit breaker in the switch panel. Both the oil temperature and oil pressure transmitters are transmission
mounted and each monitors its respective transmission operating parameter. The electrical signal output of each
transmitter is sent directly to the corresponding gauge which, in turn, produces the indicated value as a function of
the input provided.
The TRANSMISSION FILTER CLOGGED indicator receives system power (+24 -- 28 V dc) supplied from the mas-
ter relay through a 20--amp circuit breaker in the hydraulic control panel. The transmission filter switch is part of the
transmission filter and closes when the filter becomes clogged. As a result, a ground is applied to the indicator that
completes the circuit to light the TRANSMITTER FILTER CLOGGED indicator LED.
Hydraulic system gauges and indicator circuits include the LOW OIL LEVEL, CHARGE FILTER, RETURN FILTER,
and MAX OIL TEMP EXCEEDED (225° F) indicators; the HYDRAULIC OIL TEMPERATURE gauge; the liquid lev-
el sensor; charge filter switch circuit; return filter switch circuit; hydraulic high temperature switch circuit; hydraulic
oil temperature transmitter; a 20--amp circuit breaker; a 15--amp circuit breaker, and related electrical wiring.
All of the hydraulic indicators and gauge become operable when the MASTER switch is turned ON; however, the
MAX OIL TEMP EXCEEDED (225° F) indicator and the HYDRAULIC OIL TEMPERATURE gauge normally oper-
ate only when the hydraulic system is in operation. Again, an exception would be if the system was just disengaged
and hydraulic oil is still hot. The hydraulic LOW OIL LEVEL indicator lights whenever oil in the reservoir falls below
the prism of the liquid level sensor. The CHARGE FILTER, RETURN FILTER, and MAX OIL TEMP EXCEEDED
(225° F) are lit when the respective filter is clogged or the hydraulic oil temperature exceeds 225° F. The HY-
DRAULIC OIL TEMPERATURE gauge indicates the current hydraulic oil temperature.
System power (+24 -- 28 V dc) is supplied to the LOW OIL LEVEL indicator from the master relay through the
20--amp circuit breaker on the hydraulic control panel. System power is also supplied to the liquid level sensor
through the 15--amp circuit breaker. The low oil level sensor monitors the hydraulic oil level and senses a low level
condition. When this occurs, a ground is applied to the indicator to complete the electrical circuit and light the LOW
OIL LEVEL indicator LED. The CHARGE FILTER, RETURN FILTER, and MAX OIL TEMP EXCEEDED (225°F)
indicators are all connected directly to ground at hydraulic control panel. In this case, system power (+24 -- 28 V
dc) is applied to respective switches through the 15--amp circuit breaker on the hydraulic control panel. The charge
filter switch and return filter switch are part of their respective filter assemblies and close when the filter becomes
clogged. This connects system power to the applicable indicator to complete the circuit and light the LED. The hy-
draulic high temperature switch is mounted in the reservoir and closes when the oil temperature reaches 225 + 7°
F. As a result, system power is applied through the switch to the indicator to light the indicator LED. System power
is applied through the 20--amp circuit breaker to HYDRAULIC OIL TEMPERATURE gauge. The hydraulic oil tem-
perature transmitter is also mounted in the reservoir and monitors the hydraulic oil temperature. The transmitter
produces an electrical signal output that is supplied to the gauge. The gauge, in turn, indicates the current hydraulic
oil temperature as a function of the signal input.
The relationship of all of the monitoring circuits is shown in the following diagram.