Valve Operation; Switch State - Grundfos UP-ZV Instrucciones De Instalación Y Funcionamiento

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7. Valve operation

• The valve is an NC (normally
closed) type of valve, i.e. it is
closed when no power is
applied.
Without power Port "A"* closed
With power Port "A"* opened
Manually opened Port "A"* opened
* 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
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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.
Valve actuator Switch contacts
Closed Open
Open Closed
Manually open Closed