Doosan NHP10-425WCU-EU-FX-T3, Operation And Maintenance Manual

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Operating & Maintenance Manual Operating Instructions
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9. If a check valve is installed at the customer header, an additional pressure
signal line must be used to provide the unit control system with air pressure on
the plant-side of the check valve. One pressure signal line must be plumbed to
each machine. Each machine must have remote pressure selection through
INTELLISYS Controller User Options Menu.
10. If no check valve is installed at the customer header, plant air pressure will be
sensed in the on-board discharge pipe. Therefore, it is not necessary to install
the additional pressure sense line. Note: the NHP1500 unit has a check valve
to prevent backflow of plant air into the airend when the machine is idling or
shutdown.
11. Make a final inspection of the machines and all connections before starting the
units. Insure that all connections are tight and that proper hose restraining
cables and isolation valves are installed.
Setting up the Plant Air Pressure Signal
A separate plant air pressure signal line must be used when a check valve is installed at the
customer plant air header and if one of the two automatic line pressure modulation modes is
to be used. This allows each machine to automatically modulate as required to maintain the
desired plant air pressure. Use the following guidelines in installing this signal air line.
1. Install a hose restraining cable at each end of the signal pressure line to
prevent accidental hose whipping.
2. Connect a #4 pressure hose (1/4”) from a connection port on the plant air side
of the check valve to each machine. Note; This signal air line should be
maintained as short as possible for optimum response to changing plant air
pressure.
3. Install an isolation valve at the pressure source to each signal air line. This
allows a machine to be moved without affecting operation of other machines.
4. Connect the #4 hose to the signal air port on each machine. This port is located
above the discharge valve on the machine and is factory-fitted with a -4 JIC
plug. Remove the pipe cap and install #4 hose with -4 JIC connections.
5. It will be necessary to program the INTELLISYS Controller to use this pressure
port for pressure control and regulation. These instructions are provided in
“USER OPTIONS MENU”.
NOTE: When the Controller is turned on, the default selection is chosen.