Algas SDI VAPORAIRE M-Series, Operation & Maintenance Manual

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Operation
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Algas-SDI Operations & Maintenance Manual – P/N - 54264
DISCRETE OUTPUT
The PLC uses the 10 discrete outputs to control the mixing system via
interposing relays (IR).
VAPORAIREs that require more than 8 venturis will have an additional Output
Module attached to the PLC.
The discrete outputs are as follows:
O-0 -
(IR1 relay) Mixer run status
O-5 -
(IR6 relay) Venturi solenoid #4
O-1 -
(IR2 relay) Vapor inlet solenoid
O-6 -
(IR7 relay) Venturi solenoid #5
O-2 -
(IR3 relay) Venturi solenoid #1
O-7 -
(IR8 relay) Venturi solenoid #6
O-3 -
(IR4 relay) Venturi solenoid #2
O-8 -
(IR9 relay) Venturi solenoid #7
O-4 -
(IR5 relay) Venturi solenoid #3
O-9 -
(IR10 relay) Venturi solenoid #8
PRESSURE ADJUSTMENTS
NOTE
Pressure switches are set at the factory and do not require any
adjustment.
The following four subsections discuss pressure adjustments to the mixing
system.
With the LPG vaporizer at operating temperature, put a load or flare stack on the
system so at least one venturi is cycling. Note the number of venturis that are
not cycling. Note the high and low cycling pressure in the surge/accumulator
tank.
MIXED GAS OPERATING PRESSURE CONTROL SETPOINT: TRIMPOT MODULE(C)
The mixed gas pressure setpoint is adjusted using potentiometers
CH0
and
CH3
on the Trimpot module(C). Potentiometer
CH0
is the course setpoint adjustment
and potentiometer
CH3
is the fine setpoint adjustment. A miniature adjusting
screwdriver is used for the adjustments and is provided with the system.
For the adjustment ranges of each potentiometer
Refer to Table 2.
When making pressure adjustments, adjust the pressure as close as possible
using the coarse adjustment,
CH0
, then switch to the fine adjustment,
CH3
, to
obtain greater accuracy.
Adjust the setpoint so that the lowest pressure observed in the
surge/accumulator tank with all the venturis on is the required delivery pressure.
NOTE
The Mixed Gas pressure setpoint must be adjusted with the system
running under load.