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6.3
Speed Sensing
The speed sensing menu allows you to select the source to use for sensing the rotational
speed of the engine. There are three options to choose from:
1.
J1939 Input
– If the engine/generator comes equipped with an engine control
module (ECM) that supports the J1939 protocol then the GSC400 can obtain the
engine speed from the ECM.
2.
Magnetic Pickup
– If the engine/generator is equipped with a magnetic pickup
sensor then the sensor can be connected to the SPEED 1 and SPEED 2 spade
terminals on the GSC400.
3.
Generator Output
– The GSC400 can also determine the engine speed indirectly
from the generator frequency. The voltage source of the generator must be
connected to the SPEED 1 and SPEED 2 terminals.
Over-speed warnings and failures
as well as
under-speed warnings and failures
can
be set from the menu in terms of RPM. The warnings and failures apply to all three
options above.
6.3.1
Rated Speed
For the magnetic pickup and generator output options you must select the rated
frequency and rated speed.
The GSC400 uses these values together to calculate the
engine speed from the magnetic input or generator output.
The
rated speed
is the speed (in revolutions per minute, RPM) the engine runs at when
producing power. For example some generators run at 1800RPM while others run at
3600RPM.
The
rated frequency
is usually either 50Hz or 60Hz. It is the frequency of the generator
output when producing power. For a magnetic input the rated frequency is determined by
the number of teeth on the flywheel and is calculated by:
Rated frequency = (Number of teeth x Rated Speed) / 60
For the generator output option the rated frequency is normally the frequency of the
generator: 50Hz or 60Hz.
Summary of Contents for GSC400 Series
Page 15: ...Figure 4 General GSC400 System Wiring Diagram ...
Page 16: ...Figure 5 Digital IO Example ...
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