Product Overview

Operating principle
The Z-one actuator has a synchronous motor that winds the return
spring and moves the valve paddle to the desired position. When
power is removed the actuator spring returns the valve paddle. The
Zone actuator is equipped with or without auxiliary micro-switch.
Operation of normally closed valve
2-way 3-way
N.C. without power Port “A” closed Port “A” closed
Port “B” open
Port “AB” open
N.C. opened with power Port “A” open Port “A” open
Port “B” closed
Port “AB” open
N.C. manually opened Port “A” open Port “A” open
Port “B” open
Port “AB” open
2-way
(with the power off,
passage A is closed, when
using a normally closed
actuator)
2-way installed on the ow side
3-way
(with the power off,
passage A is closed)
AB
AB
AB
AB
LOAD
2-way installed on the return side
AB
L O AD
3-way installed on the ow side as a
diverting valve conguration
BA
LOAD
AB
3-way installed on the return side as a
mixing valve congeration
BA
LOAD
AB
BA
(
NC
)
AB
AB
(
NC
)(
NO
)
Construction details
• Auxiliary micro-switch
The actuator contains an auxiliary micro-
switch to operate other devices. The 24 V
actuators use a sealed reed switch, which
has been produced specifically for use with
relays, boiler contacts (TT) and DDC systems.
It requires no minimum current load. The 120
V to 277 V actuators use a conventional
micro-switch with silver contacts. The
auxiliary micro-switch is activated when the
valve is 60% open or when the actuator is
manually opened.
• Manual opening
(Normally closed actuator only)
Use the manual opening lever to open the valve.
When the power is restored the manual control
is automatically overridden. The auxiliary micro-
switch in 24 V actuators is tripped when the
unit is put into manual open position. This helps
during start up to check if the wiring is correct
without firing the valve electrically with the
thermostat. Note: The manual open lever travels
through nearly all of the actuator stroke, providing a good indicator of the
valve's position.
• Easy push button
A simple push of the button makes it easy to remove the actuator from
the body of the valve for maintenance or replacement operations.
Warning: the actuator can only be used with valve bodies Z2-Z3 series.
• Operation
The actuator uses a special mechanism for gradual movement of the
valve paddle which provides smooth and quiet constant operation.
Power-on full stroke run time is 60 seconds with 6 second power-off
return time eliminating the effects of water hammer.
• Innovative motion
When power is delivered to the actuator, the motor drives a series
of gears against a pre-wound torsion spring until it reaches its fully
stroked position. When power is dropped to the actuator, the torsion
spring back drives the motor and gear train until the unit returns to
its normal position. A lost motion mechanism disengages the motor
from the gear train at the end of stroke to prevent the impact that
would occur in directly coupled gears. This allows the Z-one actuator
to have high spring force resulting in higher close-off pressures without
compromising motor and gear longevity.