systems, such as the fuel system and the exhaust
2. Motor-driven generator test set: 28-volt dc.
gas cooling system.
3. Motor-alternator test set: 115-volt ac, one-
phase, 400-Hz.
Intercommunication System
Electric power, developed by any test engine
The intercommunication system consists of an
eight-station intercom master in the control room,
used for test purposes. If power is required by the
a suitable amplifying system, and two remote
applicable engine test instructions, a water-cooled
stations equipped with trumpets and micro-
load bank provides for application of a token
phones. The six spare station switches at the
master control are not used as installed. The
heater elements.
master unit is equipped with a volume control,
a push-to-talk button, and push-to-talk lock
Engine Starting and Ignition System
button. Remote stations are equipped with push-
The starting of a jet engine or any other type
to-talk buttons only. Station No. 1 is located in
of gas turbine engine requires that the engine be
the test cell; station No. 2 is located at the test
rotated at a speed that will provide sufficient air
cell observation port.
for the required fuel-air ratio. Provisions are made
Electrical Power Systems
for energizing the ignition system to fire the spark
(igniter) plugs at the proper time, and for the
Three primary sources of electric power are
engine to be accelerated until the power developed
provided for the test facility. They are as follows:
by the turbine is adequate for self-sustained
rotation. Initial rotation of the engine during
1. Main service to facility: 120/208-volt ac,
starting may be accomplished by use of either an
three-phase, 60-Hz, four-wire.
Figure 10-20.-Portable universal engine runup test system.
10-24