More information
See
GENSET controller
,
GENSET controller principles
,
Running detection
for the parameter to configure the number
of teeth for the MPU.
Notes on an MPU input
The MPU input terminal connections on the DEIF equipment can be changed around without any problem.
If an MPU is used, a wire break can be detected and activate an alarm.
13.9.10 W input characteristics
The W input is a signal from one of the
phases of the generator, or from an NPN/
PNP. This input can be useful during
startup, when the generator frequency is
too low to be a reliable indication of genset
speed.
By default, the W input is used as a backup
running detection. However, the W input
can be used as the primary running
detection.
Figure 13.3
W voltage-time graph
Voltage
[V]
Time
[s]
0
Figure 13.4
NPN/PNP (Hall sensor) voltage-time graph
Voltage
[V]
Time
[s]
0
INFO
You cannot use the MPU and W input at the same time. That is, if you use the W input, you cannot also use the MPU input.
Parameters
The W input is an oscillating signal. Use the generator gear ratio and the number of fields in the generator to configure a "number of
teeth" to convert the wave to the engine speed.
More information
See
GENSET controller
,
GENSET controller principles
,
Running detection
for the parameter to configure the "number
of teeth".
Notes on a W input
The engine speed calculated from the W input can differ from the actual engine speed. The accuracy depends on the genset design
and is producer-specific.
Notes on an NPN/PNP input
NPN/PNP detectors include a transistor that is powered by a direct current supply, and produce a square wave signal.
DESIGNER'S HANDBOOK 4189340911K UK
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