Conair GB - Manual (Page 55)

The last digit determines the adjustment rate. Zero in the last
position means make the full adjustment immediately. Any value from 1
to 9 indicates the percentage adjustment that will be made each cycle
when the level sensor condition changes.
See RHL below for examples.
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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 of one
selected regrind component if optional level sensors in the regrind
hopper indicate high or low conditions. The component to be changed is
determined by the first digit of the ROV parameter above.
NOTE: The component being controlled is ALWAYS automatically assigned
to the bottom set of thumbwheel switches.
If set to all zeros (RHL 00000), then this parameter is ignored.
ROV alters the way RHL is interpreted.
If the last digit of ROV = 0, (ROV x0000), then RHL numbers indicate
NEW settings that are to be run when regrind level is high or low.
If the last digit of ROV = 1 to 9 (ROV x0001) to (ROV x0009), 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 10000):
In this (and all) examples, ROV is selecting component 1 as the
controlled component. (ROV 10000)
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 bottom 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.
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