I/P Transducer Kit
15900-378
November 2021
4.
Remove installed parts. Refer to the figure on page 3 as needed.
•
760P: Remove the sealing plate screw, sealing plate and two O-rings (the O-rings may adhere to the back
of the sealing plate).
•
760E: Disconnect two signal input wires from the I/P transducer. Remove the 10-32 screw securing the
transducer and remove the transducer and I/P manifold. Remove and discard two O-rings from the I/P
manifold and two from recessed seats in the positioner body.
5.
Place two new O-rings in the recessed seats in the positioner body and two in the I/P manifold. A very small
amount of O-ring grease
1
may be applied to the O-rings to assist sealing. Install the manifold and the new I/P
transducer. Fasten with the supplied 10-32 x 2-1/4 screw.
•
760P: Go to Step 6.
•
760E: Go to Step 10.
6.
760P: To the outside of the positioner near the conduit connection, attach the metal clamping plate with an 8-32
x .375 screw and external tooth lockwasher.
7.
760P: Inside the positioner near the conduit connection, install the 10-32 x 3/8 slotted/hex head ground screw
and terminal washer.
8.
760P: Loosely install the plastic wire clamp and 8-32 x 1/4 binding head screw.
9.
760P: Apply a small amount of non-hardening pipe sealant to the supplied pipe plug. Thread the pipe plug into
the “I” input port. Tighten to 12 ft-lb. (16.3 Nm) maximum
.
10.
Attach the input leads (recommend 22 AWG shielded, twisted pair wire) to the + and - connections of the I/P
transducer terminal strip. Connect the shield to the ground screw inside the positioner. The wires should enter
the positioner through the conduit connection and be routed through the wire clamp (see the figure). Tighten the
wire clamp mounting screw as needed.
11.
Verify I/P operation and positioner calibration. Refer to Section 4 Calibration in SD760.
12.
Install the positioner cover, tighten the four screws to 20 in. lbs (2.3 N m), and return the positioner to service.
13.
760P: As needed, attach to the unit an installer supplied label or tag to identify the positioner as a Model 760E.
14.
When installing the positioner:
•
Connect a ground wire to the external ground screw adjacent to the conduit connection.
•
Connect I/P input wires to a 4-20 mA signal source.
•
Reconnect items removed in steps 1 and 2.
CAUTION
Make sure that the I/P O-rings are in place and not leaking into the enclosure. If instrument air leaks into the
enclosure to a degree that cannot be properly vented, then pressure will build up inside of the enclosure and if the
leakage is extreme, the cover gasket could be expelled. Before installing the cover, verify that there is no evidence
of air leakage coming from the O-rings (e.g. unusual noise, draft). After the cover is installed, the sound of venting
air emanating from the back of the positioner may indicate the presence of elevated pressure inside the housing. If
this occurs, disconnect external pressure sources and allow the pressure to fully vent before attempting any further
repairs.
