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Typical Valve Proving System Function
Valve proving consists of monitoring the pressure in the space
between two shutoff valves, MV1 (upstream) and MV2
(downstream). The valve proving function, identified by letters
A through F, operates as follows:
The tolerance on all valve proving timing values is ±10%.
The following are steps performed during valve proving tests.
This section is for background information and does not define
the exact behavioral requirements.
A. MV2 is commanded to be open while MV1 remains
closed; to depressurize the space. After 4 seconds, MV2 is
commanded closed again.
B. This is followed by a three second delay during which
the valve proving pressure switch (VPS) is ignored.
Table 6. Honeywell Pressure Switch Selection for Valve Proving System.
1
Model Number
Pressure Range
C6097A1004
0.4 to 5 in. wc
C6097A1053
3 to 21 in. wc
C6097A1061
C6097A1079
12 to 60 in. wc
C6097A1087
C6097A1129
1.5 to 7 psi
C6097A1137
C6097A1210
0.4 to 4 in. wc
Pressure Switch Selection
1. Determine the maximum operating inlet pressure for the
upstream valve; for example, 5.0 psi (140 in. wc).
2. Divide the inlet pressure by two (2.5 psi [70 in. wc], for
example).
3. From column 2 in Table 6 find the operating range upper
limit that is closest to but greater than the inlet pressure
divided by two. In the example given, the possible
selections from column 1 are the C6097A1129 and
C6097A1137 with an operating range upper limit of 7
psi. (The C6097A1079 and C6097A1087 with an upper
limit of 60 in. wc are close, but 60 in. wc is less than the
70 in. wc minimum, so the next higher range must be
selected.)
4. From column 6, select the preferred mounting type, 1/4
in. NPT or Flange. For example, if a flange mount is
required, the pressure switch choice from column 1
would be the C6097A1137.
Pressure Switch Installation and Adjustment
1. Refer to the instructions for the C6097A Pressure
Switch, form number 65-0237.
2. Install the C6097A Pressure Switch according to the
instructions.
RM7800L1087; RM7840G1022,L1075; EC7840L1014 RELAY MODULES WITH VALVE PROVING
2
3
Maximum
Operating
Differential
(Additive)
0.24 in. wc
0.48 in. wc
2.4 in. wc
0.3 psi
0.24 in. wc
C. Thereafter, the VPS is monitored for the duration of the
valve proving test time and, if it turns on, then a lockout
occurs. (Because the gas pressure has increased due to a
leaky upstream valve.) (Low pressure test.)
D. MV1 is commanded to be open while MV2 remains
closed, to pressurize the space. After 4 seconds, MV1 is
commanded closed again.
E. This is followed by a three second delay, during which
the valve proving pressure switch (VPS) is ignored.
F. Thereafter, the VPS is monitored for the duration of the
valve proving test time and, if it turns off, then a lockout
occurs. (Because the gas pressure has decreased due to a
leaky downstream valve.) (High pressure test.)
Pressure Switches for Valve Proving System
The Valve Proving System requires a pressure switch to be
installed to monitor the pressure in the internal space between
the two shutoff valves. Recommended pressure switches are
the following Honeywell non-manual reset models:
4
Maximum
Continuous Rated
Pressure (psi)
2.9
5.0
9.3
2.9
3. Adjust the setpoint to 50% of the maximum operating
inlet pressure for the upstream valve.
4. Complete the operation and checkout procedures in the
instructions.
Setup (Programming) of Valve Proving
Function
Prior to setup of the Valve Proving Function, follow the
procedures in the appendix to complete the worksheet and
obtain the Valve Proving Test Time.
An S7800A1142 Keyboard Display Module (KDM) is required
for this setup.
System operation requires the Valve Proving function setup
and demand input must be connected to terminal 17.
NOTE: The S7800A1142 Keyboard Display is NOT supplied
on RM7840G,L device.
When the RM7800L/40L, EC7840L,G is installed and
powered, "STANDBY" will be shown on the first line of the
display.
13
5
Switch Action at
Setpoint
Mounting Type
Breaks N.O. to C
1/4 in. NPT
connection on
pressure fall.
Flange
1/4 in. NPT
Flange
1/4 in. NPT
Flange
6
66-1162—2
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