Fail-Safe Action; Communication - Samson 5827 Mounting And Operating Instructions

Design and principle of operation

3.1 Fail-safe action

The actuator version with fail-safe action
contains a spring assembly (8, see Fig. 3-1
on page 3-1) and an electromagnet. The
actuator is moved by the force of the spring
to the fail-safe position when the electromag-
net (terminals L and N) is de-energized. The
direction of action depends on the actuator
version and cannot be reversed.
The actuator is available with the following
fail-safe actions:
Actuator stem extends: upon supply voltage
failure, the actuator stem extends.
Actuator stem retracts: upon supply voltage
failure, the actuator stem retracts.
NOTICE
!
Increased wear and shortened service life
of the actuator.
Î Do not use the fail-safe action to control
the valve position.
The actuator version with fail-safe action
does not have a handwheel (2) on the front
housing cover. Manual override is possible,
after removing the front cover, using a 4 mm
Allen key. The actuator returns to its original
position as soon as the Allen key is released.
Testing according to DIN EN 14597
The Type 5827 Electric Actuator with fail-
safe action "actuator stem extends" is tested
by the German technical surveillance associ-
ation TÜV according to DIN EN 14597 in
combination with different SAMSON valves
(the register number is available on request).
3-2

3.2 Communication

Serial interface
The actuator is fitted with an RS-232 serial
interface. This allows communication with
TROVIS-VIEW using SSP protocol (see
Fig. 3-2).
Note
The serial interface is exclusively intended for
servicing purposes. It must only be used
temporarily and not permanently.
NOTICE
!
Risk of damage to the electric actuator due
to overvoltage.
The serial interface of the electric actuator is
not fitted with a surge protector.
Î Ensure that surge protection is provided
on connecting a cable.
EB 5827-2 EN