Product Overview

Operating principle
When the power supply is OFF, the device (actuator + valve) is
“normally closed” with the obturator (1) lying against its seat.
With power, the valve opens thanks to the action of a wax
thermostatic expansion element (2) governed directly by a PTC
resistor (3).
Construction details
The 6563 series thermo-electric actuator is equipped with an
automatic valve opening position indicator, a knob for opening the
valve manually and a mechanism for returning to automatic mode if
the electricity supply is restored.
The control knob for manual opening and the automatic return from
the manual to the automatic position is particularly useful when
testing or servicing the system if:
- hydraulic tests need to be carried out without necessarily having
to connect and power up the controls.
- the knob is left in the manual position at the end of the tests. In this
case the control automatically reverts to automatic operation
when the system is electrically put into operation.
23
1
Using the thermo-electric actuator
1. Normal operation of the
actuator in automatic mode.
In automatic mode, when the thermo-electric actuator is
electrically powered, it opens the valve.
Opening is displayed by the central disc rising on the top of the
knob and by the presence of the green circular indicator.
3. Automatic return from manual to automatic position.
When the actuator is powered in the manual position, an internal
mechanism enables automatic release from this position and the
return to normal operation.
A few seconds after powering up, the knob will automatically
return to the “AUTO” position and the opening indicator will stay
on the open position (green).
˜
OFF
˜
ON
˜
ON
Valve in by-pass position
2. Using the knob to open the valve manually:
Turn the knob on the top of the actuator anticlockwise until its
limit stop trips and the arrow symbols and overlap.
To close the valve manually and restore automatic operation of
the device, turn the knob clockwise onto “AUTO”.
Note: On the series equipped with an auxiliary microswitch,
in the manual opening position the micro contact is closed.