Instruction manual

41
Type 1098-EGR Upstream or Downstream “Wide-Open” Monitor
A6789
INLET PRESSURE
OUTLET PRESSURE
LOADING PRESSURE
INTERMEDIATE PRESSURE
ATMOSPHERIC PRESSURE
September 2006
Type 1098-EGR
monitor overpressure proteCtion
TYPE 1098H (PILOT-OPERATED) MONITOR
PILOT SUPPLY REGULATOR
6350 SERIES PILOT
COMMUNITY SYSTEM MAP
TYPE 627M (DIRECT-OPERATED) MONITOR
Monitoring is overpressure control by containment. When the
working pressure reducing valve ceases to control the pressure,
a second regulator installed in series, which has been sensing
the downstream pressure, goes into operation to maintain the
downstream pressure at a slightly higher than normal pressure.
The monitoring concept is gaining in popularity, especially in
low-pressure systems, because very accurate relay points permit
reasonably close settings of the working and monitoring regulators.
When selecting regulators for use in a monitor system, the upstream
regulator must have a control line. When determining the capacity
of a monitor system you will get approximately 70% to 73% of the
capacity of a single regulator when using the same regulator for both
regulators in the system.
Fisher
®
offers a wide variety of products for monitor applications.
Provided for your reference below is a list of commonly used
regulators for various capacity requirements. Note that pilot-
operated regulators may be used in conjunction with direct-operated
regulators in monitor applications, depending on the application
requirement. Please call your local LP-Gas Equipment Distributor to
review your monitor requirements.
The major advantage is that there is no venting to atmosphere.
During an overpressure situation, monitoring keeps the customer
on line and keeps the downstream pressure relatively close to the
setpoint of the working regulator. Testing is relatively easy and
safe. To perform a periodic test on a monitor, increase the outlet set
pressure of the working device and watch the pressure to determine
if the monitor takes over.
Typical Wide-Open Monitor System
OPERATING
REGULATOR
ORIFICE SIZE
BODY SIZE,
INCH
MONITOR
REGULATOR
ORIFICE SIZE
BODY SIZE,
INCH
REGULATING CAPACITY
(1)
Inch mm Inch mm BTU/hour SCMH
Type 627-5810 3/8 9.53 3/4 NPT Type 627M-421 1/2 12.7 3/4 NPT 5,750,000 64.6
Type 627-6210 1/2 12.7 3/4 NPT Type 627M-421 1/2 12.7 3/4 NPT 7,050,000 79.2
Type 627-7710 1/2 12.7 1 NPT Type 627M-471 1/2 12.7 1 NPT 7,050,000 79.2
Type 630-104/78 1/2 12.7 2 NPT Type 627M-267 1/2 12.7 2 NPT 8,400,000 94.4
Type 630-104/78 1/2 12.7 2 NPT Type 99M-504PH 1-1/8 28.6 2 NPT 13,500,000 152
Type 99-504PH 1-1/8 28.6 2 NPT Type 99M-504PH 1-1/8 28.6 2 NPT 42,650,000 479
Type 99-504PH 1-1/8 28.6 2 NPT Type 1098 2-3/8 60.3 2 NPT 54,500,000 612
Type 1098 2-3/8 60.3 2 NPT Type 1098 2-3/8 60.3 2 NPT 136,900,000 1538
Type 1098 2-3/8 60.3 3 NPT Type 1098 3-3/8 85.7 3 NPT 283,700,000 3187
Type 1098 2-3/8 60.3 4 NPT Type 1098 4-3/8 111 4 NPT 437,800,000 4918
1. Capacities are based on 30 psig / 2.1 bar in and 8 psig / 0.55 bar out.
INLET PRESSURE
OUTLET PRESSURE
INTERMEDIATE PRESSURE
ATMOSPHERIC PRESSURE
LOADING PRESSURE
Type 1098-EGR Upstream or Downstream “Wide-Open” Monitor
A6789
INLET PRESSURE
OUTLET PRESSURE
LOADING PRESSURE
INTERMEDIATE PRESSURE
ATMOSPHERIC PRESSURE
September 2006
Type 1098-EGR
OR
Integral Two-Stage
at Each House
VaporLiquid
First Stage
Regulators
10 PSI
Set Point
Second
Stage
at Each House
11” WC
Set Point
EPR
EPR
Emergency
Shutoff Valve (ESV)
C477
Jet Bleed
Internal™
Valve
R622
R222
R622H
99
R632A
CS803
1098
H282
R232E
CnK
H282
H28
2
CS803
R232E