Installation Guide - Position Transducers
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with slot cable exits, when the displacement cable is cycled, it should be
kept in a position such that it does not drag on any part of the cable exit slot it
passes through. This advice is for both set-up and use of the product. It is also
important to keep the cable in line with the drum (pulley) groove. Doing so will keep
the cable in the groove, preventing it from jumping track and getting jammed
internally. See Figure 3.
Figure 3
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Do not open the product. The power spring can quickly unwind and cause injury. The warranty is voided for products
that have been opened.
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Do not travel past the range stated on the product's
. Permanent damage will occur.
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When operating in a wet environment, if possible, ensure the displacement cable is pointing down to avoid any liquids
streaming into the product from the displacement cable. In all environments and to the extent possible, ensure the
displacement cable is extracting and retracting in line with the cable exit. A mis-aligned displacement cable reduces the
displacement cable life.
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Extract and retract (cycle) the displacement cable 2-3 times over the full design range of the position transducer. This
cycling allows the displacement cable and spring to settle. Any zero and span controls (trim potentiometers) can be
adjusted after the cycling is completed.
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Do not use these position transducers in safety-critical applications where malfunction or total failure of the sensor
may cause danger for man or machine.
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Position transducers that require repair should be repaired only by Firstmark Controls. To avoid risk of injury and
improper handling do not try to repair position transducers yourself.
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Do not touch electrical connector pins in operation.
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Do not oil nor lubricate the displacement cable.
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The displacement cable travel should be inline with the displacement cable exit axis.
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Displacement cable misalignment should be minimized.
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Do not drag the displacement cable along objects.
5. Analog-Output Position Transducers
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Unless otherwise specified, all analog-output position transducers have either conductive plastic or hybrid resistive
elements. While these potentiometers give higher accuracy, infinite resolution, and long life, it also means they are best
used as voltage dividers. Use of these products as rheostats (resistance change measurement) is not recommended.
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Multi-turn potentiometers have a fragile internal guide (see Figure 4). This guide
will damage easily if the displacement cable is taken to the minimum or maximum
limits of travel with excessive force. This guide will not take much abuse and, if
broken, will render the potentiometer non-functional and non-repairable. The internal
guide endpoints should not be used as physical stops for the position transducer.
When setting up and using the position transducer, allow enough cable travel so the
cable motion range is within both stops and not touching either one of them.
Figure 4
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