EB 5866 EN 3-3
Design and principle of operation
3.2 Versions
Electric actuators
The electric actuators can be controlled
either using a three-step signal or, in the
version with positioner, with continuous
signals adjustable in the range from 0 to
20mA or from 0 to 10V. Various electrical
accessories can be optionally installed.
Type5825, Type5827-A and Type5827-E
Actuators are able to perform a fail-safe ac-
tion. Refer to section Table 3-1.
Electric actuators with process controllers
Electric actuators with process controller are
a combination of an electric actuator and a
digital process controller. The
TROVIS5757-3, TROVIS5724-3 and
TROVIS5725-3 Electric Actuators with
Process Controller are suitable for DHW
applications. TROVIS5757-7 is suitable for
heating and cooling applications.
TROVIS5724-8 and TROVIS5725-8 have
two PID control modules and are ready-
wired for heating and cooling applications.
TROVIS5725-3 and TROVIS5725-8
Actuators are able to perform a fail-safe
action. Refer to section Table 3-1.
Pneumatic actuators
The Type2780-1 Pneumatic Actuator uses a
control signal from 0.4 to 1bar and
Type2780-2 uses a control signal from 0.4
to 2bar which is applied to the signal pres-
sure connection.
The pneumatic actuators require a supply
pressure of at least 0.2bar above the maxi-
mum bench range. All actuators are avail-
able for fail-safe action "Actuator stem ex-
tends (FA)" or "Actuator stem retracts (FE)".