Cleveland Motion Controls ULTRA ISC SERIES SLIM CELL TRANSDUCER REV AA - Manual (Page 20)

U LTRA ISC S ERIES S LIM C ELL T RANSDUCER MAN-70434-0 R EV AA
2.5 P OTENTIOMETERS A DJUSTMENTS (I F N EEDED )
The gain and zero adjustments are factory preset but accessible by the user for adjustment if
absolutely necessary. Adjustment holes to access these potentiometers are visible on the side of the housing.
Adjustments can be made by removing the sticker around the amplifier enclosure. Use Figure 3 to locate the
zero and gain adjustment holes
The Table C lists these potentiometers, their reference designator, and a description of their functions. For
information on the correct adjustment tool to use, refer to section 2.5.1 in this document.
Potentiometer
Reference
Designator
Function
GAIN P2
This potentiometer is preset but accessible by the user for adjustment if
absolutely necessary. It provides a 10:1 “vernier” adjustment of the amplifier
gain. It is a multi-turn potentiometer, with clockwise rotation causing an
increase in amplifier gain. When turned fully counter clockwise, the
potentiometer causes the amplifier stage to provide the minimum gain.
ZERO P1
This potentiometer is preset but accessible by the user for adjustment if
absolutely necessary. It provides a zero (offset) adjustment. It is a multi-
turn potentiometer, with clockwise rotation causing a positive shift in the
analog outputs. It should be set mid-way prior to setting the ZERO
adjustment.
Table C Potentiometers Adjustments
2.5.1 C ORRECT A DJUSTMENT T OOLS
A small flat-bladed “jeweler’s” screwdriver is required. The overall diameter should be no larger than 0.062”
The thickness of the blade flat should be no greater than 0.012”. Ideally, a non-conductive tool (plastic or
ceramic) provides the safest approach for minimizing the generation of minute metallic shards that are made
when a metal blade accidentally scuffs the aluminum housing.
The Zero is normally adjusted first while the loadcell is in the No-Load condition (i.e. with no tension in the
web). The calibration forces are then applied to the transducer and then the gain potentiometer adjusted to
achieve the desired scale factor. It is advisable to look for a particular step change between load and no-load
conditions and adjust the step size independent of a particular zero point. Only after the desired scale factor
is achieved, is it then best to adjust the final zero point using the Zero adjustment.
Following adjustment, it is important to seal the adjustment holes for continued protection from
contamination. A small piece of adhesive backed tape can be used to reseal.
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