16
Model EA91A＆EA90A
Shrouding Screw
Terminal Box
Explosion-protected Nipple
Compound Charging Box
Conduit Tube
Insulated Wire
SUP
SUP
IMPORTANT
①Before piping, fully purge the air tube, and
completely remove water, oil, rust, and other
foreign matters.
②Always use dry clean air for supply air.
5.2 Pneumatic Piping
5.3 Electrical Wiring
⑴ The electro-pneumatic valve positioner has two
connectors for supply air (SUP) and output air
(OUT). The Rc1/4 screwed type is used for
connector.
⑵ For supply air (SUP), perform piping from the
air filter regulator.
⑶ For output air (OUT), perform piping to the
actuator.
⑷ Use ∅6/4 or ∅8/6 of general type copper tube
(MOTOYAMA adopts PVC coated copper tube as
standard.)
⑸ After completing conduit piping, check for leakage
from piping.
※If there is a possibility of the influence on the
positioner due to noise, use shielded cable for
avoiding the noise.
5.3.1 Model EA91A Electro-pneumatic Valve
Positioner (Flameproof Explosion-protected
Construction)
⑴ Connect wires in accordance with the wiring
diagram in Item 5.1.1.
⑵ The parallel pipe female thread G1/2 (PF1.2)
female screw is used for conduit connection.
⑶ Perform wiring in accordance with leading
procedure for external conduit referring to "New
Recommended Practice for Explosion-protected
Electrical Installations".
5.3.1.1 Leading Procedure for Flameproof Thread
Connecting Type of Conduit Tube
⑴ Perform thread connection securely using steel
plate conduit tube (JIS C8305) and lock nut (JIS
C8330) for steel plate conduit tube.
⑵ Place sealing fitting near leading port of conduit
tube, and make the leading opening airtight with
compound.
⑶ For connection of EA91A Electro-pneumatic Valve
Positioner with terminal box, accessories for wiring,
conduit tube of sealing fitting, etc., fix with lock nut
with more than 6 threads of effective thread
connected. Also, make the port watertight at the
same time.
5.2.1 Piping
(Flameproof Type
Sealing Fitting)
W
A
R
N
IN
G
DA(Direct Action)
RA(Reverse Action)
Example of Leading
External Conduit
OUT
OUT
