Supply Pressure Connection; Remote Set Point (Suffix Letter M) Pressure Connection - Fisher 4195 KB Series Instruction Manual

When installing process piping, follow accepted prac-
tices to ensure accurate transmission of the process
pressure to the controller. Install a three-valve bypass,
shutoff valves, vents, drains, or seal systems as need-
ed in the process pressure lines. If necessary, install a
needle valve in a process pressure sensing line to
dampen pulsations.
If the instrument is located such that the adjacent pro-
cess pressure lines are approximately horizontal, the
lines should slope downward to the instrument for liq-
uid-filled lines and upward toward the instrument for
gas-filled lines. This reduces the possibility of air be-
coming trapped in the sensor with liquid-filled lines or
of condensation becoming trapped in gas-filled lines.
The recommended slope is 1 inch per foot (83 millime-
ters per m).
If the controller is being used in conjunction with a
control valve to control pipeline pressure, connect the
process pressure line in a straight section of pipe
approximately 10 pipe diameters away from the valve
and also away from bends, elbows, and areas of ab-
normal fluid velocities. For pressure-reducing service,
the process pressure line must be connected down-
stream of the control valve. For pressure-relief service,
the process pressure line must be connected up-
stream of the control valve.

Supply Pressure Connection

WARNING
Personal injury or property damage may
occur from an uncontrolled process if
the supply medium is not clean, dry, oil-
free, or a non-corrosive gas. Industry
instrument air quality standards de-
scribe acceptable dirt, oil, and moisture
content. Due to the variability in nature
of the problems these influences can
have on pneumatic equipment, Fisher
Controls has no technical basis to rec-
ommend the level of filtration equipment
required to prevent performance degra-
dation of pneumatic equipment. A filter
or filter regulator capable of removing
particles 40 microns in diameter should
suffice for most applications. Use of
suitable filtration equipment and the es-
tablishment of a maintenance cycle to
monitor its operation is recommended.
4195KA, KB, and KC Series
5.13
10.25
(130)
(260)
13.00
(330)
1/4-18 NPT
1/4-18 NPT
CONTROLLER OUTPUT
SUPPLY PRESSURE
CONNECTION
CONNECTION
1.22
1/4-18
(31)
NPT VENT
1/4 NPT 4 HOLES
CONNECTION
NOTES:
1
1/4-18 NPT PROCESS CONNECTION (MARKED A) FOR ALL
BOURDON TUBE CONTROLLERS AND FOR THOSE CAPSULAR
ELEMENT CONTROLLERS USED IN VACUUM PRESSURE APPLICATIONS.
2
1/4-18 NPT PROCESS CONNECTION (MARKED B) FOR CAPSULAR ELEMENT
CONTROLLERS USED IN POSITIVE AND COMPOUND PRESSURE APPLICATIONS.
3 FOR THE EXTERNAL FEEDBACK CONNECTIONS (4195KB
CONTROLLERS ONLY), EITHER THE A OR B CONNECTION IS USED,
DEPENDING ON THE LOCATION OF THE PROCESS CONNECTION.
46A9765-A
A2892-4 / IL
Figure 2–5. Connection Locations
Supply pressure must be clean, dry air or noncorrosive
gas that meets the requirements of ISA Standard
S7.3-1975 (R1981). Use a suitable supply pressure
regulator to reduce the supply pressure source to the
normal operating supply pressure shown in table 1–6.
Connect supply pressure to the SUPPLY connection
on the bottom of the case, shown in figure 2–5.
Remote Set Point (suffix letter M)
Pressure Connection
If the controller has remote set point (suffix letter M),
connect the remote set point pressure to the top of the
controller case at the location shown in figure 2–5.
Use clean, dry air or noncorrosive gas. Use a 3 to 15
psig (0.2 to 1.0 bar) remote set point pressure range
for a 3 to 15 psig (0.2 to 1.0 bar) controller output sig-
nal range or a 6 to 30 psig (0.4 to 2.0 bar) remote set
point pressure range for a 6 to 30 psig (0.4 to 2.0 bar)
controller output signal range. If pressure is supplied
to the remote set point connection with a regulator, a
small bleed orifice should be placed between the regu-
lator and remote set point connection to prevent pres-
sure variations due to regulator lock-up.
4.00
(102)
2.00
5/16
(51)
UNC-28
3 HOLES
(MOUNTING)
3.44
(87)
10.04
(255)
5.80
(147)
2.56
(66)
1/4 NPT
REMOTE SET POINT
CONNECTION
INCH
(mm)
2–3