Issue
N
C.S.
04.03.20
Trading Estate Farnham Surrey England
Doc. No. TD 120
Page 13 of 25
5. SETUP (continued).
5.14 Setting Optional Angle Retransmit Span and Zero Adjustments.
The angle retransmit circuit is mounted directly underneath the positioner circuit, and its ZERO and SPAN preset pots are
accessible using a small instrument screwdriver through the two access holes in the positioner circuit (see Figure 6). Connect
the air supply, positioner signal and angle retransmit reader supply. To set the ZERO, move the positioner to its minimum
signal position (usually 4mA), and set the ZERO preset pot to give the desired retransmit current. Then set the SPAN by
moving the positioner to its maximum signal position (usually 20mA), and adjusting the SPAN pre-set pot to give the desired
retransmit current. Recheck and read just these two settings until both are correct – as the SPAN is adjusted, it has a small
effect on the ZERO reading, and vice-versa, so a few readjustments may be necessary.
The angle retransmit circuit is fitted with a jumper, which should be fitted to bridge its two pins if you want the circuit to read 4-
20mA over 45 degrees or near, rather than the usual 90 degrees. The range adjustment pot is adjustable to give ranges in
between these two values. To gain access to this jumper, it is necessary to remove the whole carrier plate assembly from the
positioner – see Section 3.1 for instructions on this.
Figure 9. EL Lid – Clear Cone Monitor Adjustment
5.15 Adjustment of Position of Optional Clearcone Monitor.
If your positioner is fitted with a Clearcone position monitor, you may need to adjust its angle to read correctly after you have
set up the positioner. The internal O-ring slides to give a coarse setting, and the shell mounting slots give a few degrees of fine
adjustment. Please note that a special version of the monitor, which has an electrically conductive surface, is fitted to IS EL
positioners.
To adjust the position of the angle scale, first unscrew the two self-tapping stainless mounting screws which hold the
transparent outer shell to the lid, and lift off the shell complete with its black mask/pointer moulding. Don't lose the screws or
the sealing O-ring which seals round the outside of the shell-lid interface.
If you have reversed the clockwise/anticlockwise sense of the positioner, you may at this stage need to replace the self
adhesive angle scale sticker with one marked in the opposite sense. Take care to stick it to the scale cone moulding
accurately.
Rotate the scale cone by sliding it round on its internal O-ring against the coupling inside it, which is located on the positioner
shaft square. This may take some effort if the O-ring has stuck on. Move it until it is reading as near correctly as you can
achieve against the pointer on the mask/pointer moulding, which you should hold in position with the outer shell mounting slots
centrally located above the screw holes in the lid. Refit the mounting screws, making sure that the mask moulding and the
sealing O-ring are well located in the outer shell moulding. Adjust the pointer position to its final position by rotating the outer
shell slots against the mounting screws, taking care to position the screws at equivalent positions in both slots so that the shell
remains central relative to the rotating parts inside, then tighten the screws to clamp it into position.
Title : Installation, Operation & Maintenance Instructions – IS Digital EL Positioner
N – AR7059 / M – AR6971 / L - AR6419 / K - AR6347 / J-AR6096 / H – AR 6082 / G – AR 5487 / F – AR 5608 / E - AR 5293
