Conair GB/ WSB - Manual (Page 54)

the system takes this to indicate that the regrind hopper is now empty,
and the controls revert back to normal.
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RHL (LEVEL SENSORS are required for this parameter to work)
(Use only if you have regrind level sensors fitted)
RHL instructs the controller to change the regrind setting if
optional level sensors in the regrind hopper indicate high or low
conditions.
If set to all zeros (RHL 00000), then this parameter is ignored.
The ROV parameter can alter the way the RHL parameter is interpreted.
If ROV = 0, (ROV 00000), then RHL numbers indicate NEW settings that
are to be run when regrind level is high or low.
If ROV = 1 to 9 (ROV 00001) to (ROV 00009), then RHL indicates upper
and lower regrind usage limits only, and regrind usage will be adjusted
slowly, to these limits, based on the ROV number.
IF ROV equals zero (ROV 00000):
If RHL is set to any value, the first 3 digits of the parameter
indicate a new Regrind setting to use when the material level is ABOVE
the HIGH level sensor; (sensor is covered). The last 2 digits indicate
a new setting to use if material level is BELOW the LOW sensor; (both
High and Low sensors are uncovered).
In other words, RHL allows the selection of a percentage that is HIGHER
then normal, and a percentage that is LOWER then normal. NORMAL is
what you put on the thumbwheel switch.
Sensors are assumed to be covered when NO signal is returned. If a
sensor is unplugged from the controller, it is read as "covered".
If you only have ONE SENSOR, it must be used as a HIGH level sensor.
The absence of a sensor is read as a covered sensor; so the absence of
the high sensor would signal the system to run at the high setting all
the time. This would not be acceptable. The absence of the LOW sensor
simple prevents the system from ever thinking it is very low. This is
acceptable.
With a high level sensor only, the system switches between the NORMAL
thumbwheel setting and the HIGH setting indicated by the first 3 digits
of the parameter. The last 2 digits have no effect, since a LOW
condition is never detected.
Sensors that we supply are wired correctly for this logic. If a
"Bindicator" or similar device is used, with a micro-switch dry contact
closure signal, then wire to the normally CLOSED contact so that the
signal OPENS when regrind covers the bindicator paddle.
The circuit board "pin outs" for each sensor are positive, ground, and
signal. If you are wiring using a dry contact closure, only the
positive and signal lines are used. When the contact is open, the
signal is pulled to ground internally through a resistor.
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