Samson 3731-5, Mounting And Operating Instructions

Page: 41 / 112

EB 8387-5 EN 41
Mounting and start-up
5.8 Reversing amplifier for
double-acting actuators
For the use with double-acting actuators, the
positioner must be fitted with a reversing am-
plifier.
We recommend using the Type 3710 Revers-
ing Amplifier (see Mounting and Operating
Instructions
u
EB 8392).
If a different reversing amplifier (item no.
1079-1118 or 1079-1119) is used, follow
the mounting instructions described in sec-
tion 5.8.1.
The following applies to all reversing amplifi-
ers:
The signal pressure of the positioner is sup-
plied at the output A
1
of the reversing ampli-
fier. An opposing pressure, which equals the
required supply pressure when added to the
pressure at A
1
, is applied at output A
2
. The
rule A
1
+ A
2
= Z applies.
A
1
: Connect output A
1
to the signal pressure
connection on the actuator that causes the
valve to open when the pressure rises.
A
2
: Connect output A
2
to the signal pressure
connection on the actuator that causes the
valve to close when the pressure rises.
A
1
1.5 1.6
1.3 1.2 1.1 1 1.6
Z
A
2
1.4
A1 A2
Z
A1
Output 38 Supply 9
Output 38
Supply
9
1.3 1.2 1.1
1 Reversing amplifiers
1.1 Special screws
1.2 Gasket
1.3 Special nuts
1.4 Rubber seal
1.5 Stopper
1.6 Filter
From the positioner
Control signals to the actuator
Fig. 11: Mounting a reversing amplifier (1079-1118 or 1079-1119)
Tip