A-8
Appendix A
Model 580A Differential Pressure Switch
BLOCK
VALVES
PRIMARY
DEVICE
BYPASS
VALVE
FILL TEE AND
VENT VALVE
FOR HOT OR
GASSY LIQUIDS
SHUT-OFF
VALVES
DPU
Figure A.8—Liquid Flow, DPU Below Run
BLOCK
VALVES
SEAL
POTS
PRIMARY
DEVICE
BYPASS
VALVE
SHUT-OFF
VALVES
DPU
Figure A.9—Corrosive Liquid Flow
DRAIN
VALVE
BLOCK
VALVE
HIGH-PRESSURE
DPU
BLOCK
VALVE
SHUT-OFF
VALVE
VENT
VALVE
SHUT-OFF
VALVE
Figure A.10—Cool Non-Condensing Liquid, DPU Level with Tank Bottom