Purge set installation
This accessory is available upon request.
1. Replace the M4x16 screws of the electronic drive unit with the CHC M4x30 screws and washers.
2. Remove the dust filter or plug from the purge.
3. Tighten the 1/8'' BSPP UNION fitting to the purge port.
4. Place the assembly onto the electronic drive unit using the CHC M4x30 screws as guidance in the
plate holes.
5. Align the 1/8'' BSPP union fittings before tightening the nut.
6. Tighten the nuts with the washers.
7. Test vacuum tightness.
Connecting the purge accessory to an inert gas supply line
This solenoid valve can be connected to an inert gas line. The inert purge flow must be present when
the pump is running.
When the pump is stopped, the solenoid valve can be closed to perform a tightness test on the equip-
ment.
To connect the solenoid valve to an inert gas line, the nitrogen supply must be clean and filtered and
must have the characteristics required (see chapter "Nitrogen characteristics").
1. Remove the plug from the solenoid valve connector.
2. Connect the inert gas line instead: 1/8 BSPP female connector.
3. Bond the connection using oleo-waterproof glue, or put PTFE sealing tape on the threads.
4. Tighten the connection, applying a maximum tightening torque of 10 N·m.
5. Adjust the inert gas pressure to obtain the desired flow (see Purge flow diagram).
5.7 Connection of the air inlet solenoid valve
This accessory is available upon request (see chapter "Accessories").
The air inlet solenoid valve (flow 11 · 10
3
sccm), is calibrated to restore the atmospheric pressure in the
pump internal volume. When isolation valves are installed on the pump inlet and exhaust, the rotor
slow-down efficiency is improved.
The air inlet solenoid valve is installed on the pump exhaust.
24 VDC power supply and air inlet valve control are the customer’s responsibility.
1
2
1 Air inlet solenoid valve
2
Dust filter
Control of the air inlet solenoid valve
The pump is reset to atmospheric pressure when the pump stops or in the event of a default stop. The
air inlet valve must be powered when the rotation speed of the pump is less than 10,000 min
-1
and an
opening command is sent to the solenoid valve.
The NC (normally closed) air inlet valve must be closed to restart the pump (note: it does not close au-
tomatically when the pump stops).
1. Connect the solenoid valve to the
PUMP EXHAUST
port of the pump (use connecting accesso-
ries of product catalog).
2. Power the solenoid valve.
3. Wire the solenoid valve control.
Installation
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