Leslie PMC-1 User Manual

APPENDIX F
TYPICAL PRESSURE CONTROL APPLICATION
FOR PMC-1 ELECTRO-PNEUMATIC CONTROLLER
A standard pressure transmitter is connected to the PMC-1 at
the transmitter input terminals. The PMC-1 provides 24VDC
power to the pressure transmitter, compares the 4-20mA
signal returned to the set point and, using a series of short
pneumatic pulses, modulates the control valve as required to
maintain the desired pressure.
The pressure transmitter is connected to the process pipe by
means of a pig tail and isolating valve. The isolating valve
provides the ability to change or calibrate the pressure
transmitter without otherwise disturbing the system. The pig
tail is important in steam applications to avoid overheating
the pressure transmitter. The loop in the pig tail maintains a
condensate buffer between the steam and the sensing
diaphragm of the pressure transmitter.
During installation, the PMC-1 is calibrated by dialing in the
upper and lower limits of the pressure transmitter. The set
point and process status can then be read directly from the
backlit LCD display in the units of measurement preferred by
the user.
15
PMC-1
Up to 100 psi
Plant air
Airset
4-20mA
24VDC
Pressure transmitter
Pigtail

Leslie PMC-1 Specifications

General

Brand	Leslie
Model	PMC-1
Category	Controller
Language	English