Masoneilan VariPak Adjustable Cv Control Valves Instruction Manual
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Insulation: If the valve is to be insulated, ensure that the
insulation does not exceed the shaded area shown in
figure 10 below.
Figure 10 - Insulation limit for a VariPak valve
3.3 Pneumatic and Electrical Circuit
(Figures 3, 11 and 12)
- On-off valve: connect the air supply line directly to the
1/8" NPT threaded connection in diaphragm cover
(137).
- Control valve with 7700P positioner (air signal):
connect the supply and instrument signal lines to the
appropriate connections on the manifold block (144)
(figure 11). Use 4 x 6 mm (1/4" O.D.) tubing.
- Control valve with 7700E positioner (electrical signal):
connect the manifold block (144) air supply line and
make the electrical connection for the I/P module (20)
(figure 12).
Use 4 x 6 mm (1/4" O.D.) tubing for the air line.
Note: Check that the supply pressure is that indicated on
the serial plate.
7700P or 7700E positioners can be installed on
both VariPak 28001 single-lever and VariPak 28002
adjustable-Cv valves.
Figure 11 - Connections with 7700P positioner
Figure 12 - Connections with 7700E positioner
3.4 Limit Switches (Figure 13)
In some cases, limit switches can be provided for the
VariPak valve, on request. These are wired and adjusted
in the factory to customer order. The black wire is
connected to either the normally open or normally
closed terminal of the upper limit switch. The black and
white wire is connected to the common terminal of this
switch. The red wire is connected to either the normally
open or normally closed terminal of the lower limit
switch.
The red and white wire is connected to the common
terminal of this switch. To adjust limit switches, loosen
their fasteners and move the valve to the required
position. Adjust the position of the switch until it trips.
Tighten fasteners (160 - 161 - 162).
Figure 13 - Limit switch installation
