User Guide

10
7. Valve operation
• The valve is an NC (normally
closed) type of valve, i.e. it is
closed when no power is
applied.
* See fig. 3 for location of Port A
and Port B.
• Automatic operation
When power is applied, the
manual lever will unlock
automatically.
• Manual operation
Slowly move the manual
opening lever to the unlocked
position. See fig. 7.
Fig. 7 Manual opening and
closing of valve
7.1 Switch state
• The end switch contacts are
open when the valve is closed.
• The switch contacts are closed
(call for heat) when the valve is
open (automatically).
• The switch contacts are also
closed when the actuator is
manually opened. This allows
the heating circulation to
function by simply manually
opening the actuator.
Without power Port “A”* closed
With power Port “A”* opened
Manually opened Port “A”* opened
TM04 7099 1510
Valve actuator Switch contacts
Closed Open
Open Closed
Manually open Closed
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