Instruction Manual
D101728X012
3710 and 3720 Positioners
September 2017
19
Figure 12. Connections
34B0693‐A
B2386‐1
OUTPUT CONNECTIONS
INPUT (SUPPLY)
CONNECTION
VENT
M20 CABLE
GLAND
RIGHT SIDE VIEW
3720 POSITIONER
TOP VIEW
INPUT
CONNECTIONS
VENT
OPENING
3710 POSITIONER
RIGHT SIDE VIEW
REAR VIEW
The conduit connection to the converter is 1/2‐14 NPT.
The positioner does not have a remote vent connection. Refer to the section on vent opening, purge option, and
actuator vent connection for instructions about a remote vent connection.
Supply Connection
WARNING
Severe personal injury or property damage may occur if the instrument supply medium 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 field office and industry instrument air quality standards for use with corrosive gas or
if you are unsure about the proper amount or method of air filtration or filter maintenance.
3720 positioners and 3722 converters do not meet third party approvals for use with natural gas as the supply pressure
medium. Use of natural gas as the supply medium can result in personal injury or property damage from fire or explosion.
Connect a clean, dry, oil‐free, noncorrosive air source to the supply connection of the positioner. Recommended
supply line size is 3/8‐inch tubing or 1/4 NPT pipe. Use of an appropriate supply air filter or filter regulator is
recommended. Refer to the positioner specifications, table 1, for supply pressure requirements.
