PRESSURE & TEMPERATURE CORRECTION
TO ACCURATELY MEASURE GASSES WITH ANY STANDARD
GAS METER, PRESSURE & TEMPERATURE MUST REMAIN
CONSTANT. ROOTS OFFERS A VARIETY OF PRODUCTS TO
CORRECT VOLUME FOR PRESSURE AND/OR TEMPERATURE
CHANGES. READINGS MUST BE CONVERTED TO STANDARD
CONDITIONS FOR BILLING.
Meter Types -
All with Digital Readout
Counter Version (CTR)
If the pressure is low (i.e., 10 inches water column) or well regulated
(i.e., ± 1% of absolute pressure), and the temperature is relatively
constant, specify the CTR version meter. Pressure and temperature
factors, according to the Perfect Gas Laws, can be applied to the
counter reading to determine the standard volume at base conditions.
Ask for Engineering Data Bulletin RM-135 for temperature and
pressure factors.
Temperature Compensated Version (TC)
The TC version meter is used when temperatures can vary significantly (5'F. approximately
equals 1% change in volume).
Meters installed outside or just after large pressure cuts are normally temperature
compensated to the base temperature of 60'F. The compensation range is from -20'F. to
+100'F. Reference tables available to determine necessity of TC The 1.5M through 16M ROOTS
Meters can be provided with temperature compensation.Instrument [)rive Versions (ID, CD,
TD)
The instrument drive version ROOTS Meters are normally used on applications where the
pressure is varying. A ROOTS Electronic Corrector for pressure compensation, ROOTS
"IMCW" (Integral Micro-corrector)
for pressure and temperature compensation, ROOTS "IMCW", can be mounted on
integral or on the instrument drive to provide the local corrected volume reading and
remote pulse outputs.
The 1.5M through 16M ROOTS Meters can be provided with a temperature compensated
instrument drive (TD)
which only necessitates the addition of a pressure corrector to get pressure and
temperature compensated volumes.
The 1.5M through 102M, and some high pressure ROOTS Meters, are available with counters
and
instrument drive(CD). The CD (ID meter with uncorrected counter on the meter) version is
standard on the 16M through 102M meters. The 1. 5M through 11 M are available with
instrument drive (ID), and all high pressure
meters are supplied with instrument drive as standard.
Electronic Transmitter Output Option (CEX )
The CEX option should be selected as an addition to
any mag-coupled meter to provide a high frequency pulse
signal for remote Totalizers, Panel Meters or other flow
computers with analog (4-20mA, 0-5VDC etc.) outputs.
The output from the CEX or MEX opens up new
possibilities in gas measurement with ROOTS Meters and is
suitable for use in process control applications. Supply voltage
12 VDC typical.
Electronic Transmitter Output Option (CPWS or CPWD)
The CPWS or CPWD option should be selected as an addition to
any mag-coupled meter to provide a solid state pulse output
signal, 10 Cu Ft/ pulse typical. This pulse may be sent to a
remote totalizer or scaleable panel meter. Supply voltage
3-30 VDC, loop current 10mA max.
ROOTS
MODEL 8C175CEXX
Modified high density pulse output
sold exclusively by:
Process Valve & Equipment Co.
Base rating: 800 ACFH
.003748 ACF per revolution
two pulses per revolution
output frequency 118.57 HZ /800CFH
533.617 pulses per ACF
pressure drop .04 to .70 inches W.C.
