Sices HS 315, Техническое руководство

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48 Technical Handbook
Some battery charger alt
ernators make available a “W” terminal that has an alternate voltage
with a frequency proportional to the rotation speed of the battery charger. The W signal is
generated inside the engine start battery recharge alternator. It is a square wave, with an
amplitude ranging from 0 to Vbatt and a frequency proportional to the engine speed but
depending on how the alternator is built and on the ratio between the diameters of the pulleys
onto which the driving belt runs.
To use the W signal, it is required:
•
Connect the W signal of the battery charger alternator to the terminal JM-7 .
•
Connect terminal JM-5 to terminal JM-6 (short circuit).
As already mentioned, the W signal frequency is proportional to the battery recharge alternator
rotational speed, and not to the engine running speed: in fact, between them there is a belt.
Therefore, you must set a ratio (parameter P.0111) to allow the controller to convert the
frequency of the W signal (battery recharge alternator revolutions per second) in engine
revolutions
per minute. This ratio depends on many factors and it is not easy to calculate. If a
frequency meter is available, simply start the engine (it will run at is rated and known speed,
i.e. 1500 rpm) and measure the W signal frequency, and then calculate the ratio. If a frequency
meter is not available, the following method can be used:
•
Set a random value for P.0111 (e.g. 15).
•
Start the engine and, when at operating speed, note the rpm value shown by the
controller.
•
Calculate the ratio between the displayed speed and the actual engine speed
(displayed/actual).
•
Multiply the value previously set in P.0111 by this ratio and set the new value.
Restarting the engine, the speed measure should be close to the actual speed. Then, manually
adjust the value P.0111 until you get the right display, considering that, for the same true
speed, the value displayed by the controller decreases when increasing P.0111. To determine
the engine speed, the generator frequency can also be used.
Leave P.0111 to 0 if W signal is not used.
Notice: if W signal is used, set P.0110 to zero.