Installation
3-6
Algas-SDI Operations and Maintenance Manual – P/N – 54702
AIR SUPPLY
1. Air filters may be required on the air supply and instrument air. The user must
determine the cleaning schedule for the filters. Dirty air will cause problems in
the mixing systems. Oil carryover must be less than 2 PPM. Particulates greater
than one micron must be removed. Temperature must be less than 130F.
Dewpoint must be 2 deg. F below the temperature of air entering the mixer.
2. An air dryer for the incoming air supply will be required if water vapor could
condense in the air supply lines.
3. A properly sized first-stage air pressure regulator is required to be installed
upstream of the mixer compressed air inlet. The air supply pipe to this regulator
must not be more than 150 psi.
VAPOR SUPPLY
1. A properly sized first-stage gas supply pressure regulator is required to be
installed upstream of the mixer LPG vapor inlet. This regulator reduces the
operating pressure to approximately 4-10 psi (0.23-0.67 kg/cm
2
) over desired
mixed gas pressure.
2. If the LPG has a heavy end content, filters must be provided upstream of the
regulator on the vapor inlet pipe to each
BLENDAIRE
. The user must
determine the cleaning schedule for the filters. A drip leg to drain the heavier
particles should be provided immediately upstream of the first stage
regulator.
3. Heat tracing must be placed over the vapor supply pipes if the ambient
temperature falls within 10°F of the dewpoint of the LPG gas. Electric heat
tracing is preferred with an appropriate controller. All heat tracing must be
suitable for the class of hazardous location in which it is to be installed.
Always consult with the appropriate authorities and all applicable codes.
MIXED GAS OUTLET
1. The temperature of the pipe must be kept above the dewpoint of the air/gas
mixture. Heat tracing over the outlet pipe may be required as well.
2. A check valve must be installed in utility gas line if it is to be connected to
utility gas main into plant.
NOTE
See the LPG gas dew points given in Appendix B
PROCESS CONTROLLERS
1. The
BLENDAIRE
comes with a local PLC control panel suitable for
hazardous area classification and a remote HMI panel suitable for General
Location.
2. The
BLENDAIRE
utilizes 4-20mA, 24 VDC to provide power and
communicate with the devices on the mixer. 120VAC is used to control safety
solenoids on the mixer.
3. See wiring Diagram for wire type and required field connections.
INSTRUMENT AIR SUPPLY
1. All safety shutoff valves and flow control valve operate on air and are closed
when the air supply is cut off if a safety shutdown is triggered.
2. An instrument air regulator installed on the mixer must be supplied with
clean, compressed instrument air of minimum 100 psi and no more than 150
psi.
