Samson 4763, Mounting And Operating Instructions

The following accessories are available:
Cable gland M 20 x 1.5
Black

Order no. 1400-6985

Blue

Order no. 1400-6986

Adapter M 20 x 1.5 to ½ NPT:
Aluminum, powder-coated

Order no. 0310-2149

3.2 Pneumatic connections

The pneumatic connections are designed as

tapped holes with ¼ NPT or ISO 2228/1-

G ¼ thread. The conventional male connec-

tions for metal and copper pipes (or plastic

hoses) can be used.

Note:

The supply air must be dry and free of any

oil and dust. Always observe the mainte-

nance instructions applicable to the con-

nected pressure reducing stations. Blow out

air lines thoroughly before connecting them.

3.2.1 Pressure gauges

We recommend attaching pressure gauges

for the supply air and signal pressure in or-

der to monitor the positioner. The parts are

listed as accessories in the table on page

20.

3.2.2 Supply pressure

The required supply pressure is determined

by the bench range and the operating direc-

tion (fail-safe action) of the actuator. The

bench range is written on the nameplate as

spring range or signal pressure range de-

pending on the type of actuator.

FA

(actua-

tor stem extends) or

FE

(actuator stem re-

tracts) or a symbol indicates the operating

direction.

Actuator stem extends (FA)

Fail-safe position Valve CLOSED

(for globe and angle valves)
Required supply pressure =

Upper bench range value + 0.2 bar,

minimum 1.4 bar.

Actuator stem retracts (FE)

Fail-safe position Valve OPEN

(for globe and angle valves)
The required supply pressure for a

tight-closing valve is roughly estimated from

the maximum signal pressure pst

max

:

pst

max

= F + d

p

A

2

4

× ×

×

p D

[bar]

d = Seat diameter [cm]

D

p = Differential pressure across valve [bar]

A = Actuator diaphragm area [cm²]
F = Upper bench range of actuator [bar]

EB 8359-2 EN

11

Connections

Fig. 6 · Electrical connection

Input

control signal

(0)4 to 20 mA