Typical Valve Proving System Function - Honeywell RM7800L1087 Installation Instructions Manual

RELAY MODULES WITH VALVE PROVING
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.
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.)
Table 6. Honeywell Pressure Switch Selection for Valve Proving System.
1
Operating
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 mini-
mum, 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.
32-00142—01
2 3
Maximum
Differential
(Additive)
0.24 in. wc
0.48 in. wc
2.4 in. wc
0.3 psi
0.24 in. wc
14
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 Switch Action at
Pressure (psi) Setpoint
2.9 Breaks N.O. to C
connection on
5.0
pressure fall.
9.3
2.9
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.
3. Adjust the setpoint to 50% of the maximum operat-
ing 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 or S7800A2142 Keyboard Display
Module (KDM) is required for this setup.
5 6
Mounting Type
1/4 in. NPT
Flange
1/4 in. NPT
Flange
1/4 in. NPT
Flange