Pressure Connections; Supply Connection - Fisher 3660 Instruction Manual

Instruction Manual
D101402X012
12. Move the pilot shaft (key 19A) to the approximate span position shown in table 8.
Note
To ensure proper positioner performance, make certain, after alignment and all tightening is completed, that there is clearance
between the face of the pilot shaft and the feedback arm.
13. Install the feedback lever assembly cover (key 19T) with cover screw (key 19U).
14. Verify the positioner action. Note the letters D and R on the flapper (key 10). If the letter D is nearest the
adjustment screw (key 18), the positioner is set for direct action. To change the positioner action, refer to the
Changing Positioner Action procedure in the Maintenance section. If the action is changed, complete the
Calibration section before putting the unit into operation.
15. Install the positioner cover (key 21) and secure with the two machine screws (key 24). Make certain the Fisher logo
reads correctly and the vent is pointing downward. Continue with the Pressure Connections section.

Pressure Connections

Installing a 3660 or 3661 positioner requires tubing and pressure fittings. The fittings, tubing, and mounting parts
required depend on the type number and optional equipment, such as filter/regulator and bypass valve. See figure 15
for the location of the positioner pressure connections.
WARNING
The positioner is capable of providing full supply pressure to connected equipment. To avoid personal injury and property
damage caused by parts bursting from system overpressure, make sure the supply pressure never exceeds the maximum
safe working pressure of any connected equipment.

Supply Connection

WARNING
Severe personal injury or property damage may occur if the instrument air supply is not clean, dry and oil‐free. While use
and regular maintenance of a filter that removes particles larger than 40 micrometers in diameter will suffice in most
applications, check with an Emerson Process Management field office and industry instrument air quality standards for use
with corrosive air or if you are unsure about the proper amount or method of air filtration or filter maintenance.
CAUTION
The O‐rings used in 3660 and 3661 positioners are made of EPDM (ethylene propylene). Use a clean, dry, oil‐free air supply
with instruments containing EPDM components. EPDM is subject to degradation when exposed to petroleum‐based
lubricants.
3660 and 3661 Positioners
September 2015
19