Data Sheet

Bulletin 71.1:CP400
6
orice or by thermal expansion of gas in the downstream
line. Token relief also provides a token or signal, in the
form of odor, that an overpressure situation is occurring.
Type CP403 Integral Monitor Operation
Type CP403 combines the operation of a conventional
two-regulator wide-open monitor set into one body, see
Figure 5. The Integral True-Monitor™ is installed on
the inlet side of the body and serves to throttle ow and
maintain an acceptable downstream pressure in the case
where the Primary regulator fails to regulate downstream
pressure. During normal operation, the Integral Monitor
is in a wide-open state as its setpoint is set higher than
the primary regulator. See Tables 6 and 7 for guidance
regarding the setpoints of the regulator and associated
integral monitor sets. If the downstream pressure should
rise to the setpoint of the internal monitor due to loss of
pressure control by the primary regulator, the integral
monitor will assume control and regulate the ow to the
downstream system. See the Type TM600 Instruction
Manual for additional details of operation. If a Token relief
is present, the token relief will relieve a small amount of
gas to the atmosphere as an indication that the Integral
Monitor is controlling the downstream pressure.
main disk against the orice seating surface. At this
point the loading regulator will continue to supply
a small amount of gas downstream that is equal to
the capacity of the bleed restriction in the diaphragm
assembly. As downstream demand decreases to zero
ow outlet pressure rises to meet the lockup pressure
of the loading regulator. This causes the loading
regulator to lockup to stop all ow downstream.
Downstream Control Line Connection
A CP400 Series regulator with an ET or EN in the type
number has a blocked throat, an O-ring stem seal and
a 3/4 NPT control line tapping in the lower diaphragm
casing, Figure 4. A regulator with a downstream
control line is used for monitoring installations or other
applications where there are equipment installed
between the regulator and the pressure control point.
The O-ring stem seal helps separate body pressure
from diaphragm case pressure on monitor installations
where leakage cannot be tolerated.
The Types CP400IT and CP400ET provide a low
capacity/token relief. Token relief provides relief from
minor overpressure caused by nicks or dents on the
Figure 4. Type CP400ET Pressure Loaded Regulator with External Pressure Registration Operational Schematic
Type CP400ET Pressure Loaded Regulator with Token Relief
M1083
January 2008
Type CP400ET
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
LOADING PRESSURE
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
LOADING PRESSURE
M1066
TYPE 67CPR PRESSURE
LOADING REGULATOR
3/4 NPT
CONTROL LINE
CONNECTION
CONTROL SPRING
CLOSING SPRING
LEVER
VALVE DISK
VALVE STEM
ORIFICE