3.2.3 Adjustment of the Switching Points of the Limit
Switches
In the MiniTOP Type 8633, the limit switches are firmly fixed to the housing.
The setting of the switch points is carried out by moving two of the cams
clamped on the switch spindle. The clamp is designed so that the cams can be
moved "by hand". An unintentional adjustment of the cams is ruled out,
however.
3.2.3.1 Adjustment of the upper switching point
When fitting the MiniTOP onto the guide piece (from the accessory set)
fixed to the process valve, guide the switch spindle through the round
opening in the centre of the see-through cover
and
Press the complete housing firmly down until it meets the stop.
In this way, the upper cam will be automatically pushed to the correct
position. A re-adjustment is not necessary. The precondition for the correct
position is, however, that the upper cam is located at the outermost end of the
spindle when the MiniTOP is fitted. The setting of a new intermediate position is
not possible.
3.2.3.2 Adjustment of the lower switching point
a) Control function A
In the case of a valve drive whose piston is at the "lower" rest position, the
correct cam position is already given by pushing the first cam up to the
guide piece (stop).
b) Control function B
In the case of a process valve drive whose piston is at the "upper" rest
position, the correct cam position will only be reached after the process
valve switched for the first time.
c) Control function I
In the case of a double-acting valve drive without a defined rest position,
the correct cam position will be reached after the first switching cycle, as
for control function B.
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MiniTOP Type 8633