<4. Operation>
4-1
IM 02C01B04-01EN
4. Operation
4.1 Zero Adjustment
4.1.1 Without Elevated or Suppressed
Zero Range
Make zero adjustment with transmitter in operating
position.
1. Adjust air supply to pressure at which
transmitter will operate.
2. Vent pressure connection. On liquid filled
system, vent at level of pressure tap.
3. Connect a 0-1.5 kgf/cm
2
or bar, 0-150 kPa, or
0-22 psi test gauge (or manometer) to OUT
connection.
4. Adjust zero screw for a 0.2 kgf/cm
2
or bar, 20
kPa, or 3 psi output.
5. Disconnect test gauge and reconnect receiver.
If necessary, change zero adjustment on
receiver so that reading is zero.
OUT connection
Test gauge
Pressure connection
Air supply
(140 kPa)
F0401.ai
Zero screw
F0402.ai
Figure 4.1
Zero Adjustment
4.1.2 With Elevated or Suppressed Zero
Range
Make zero adjustment with transmitter in operating
position.
1. Set up equipment as shown above, but do not
vent pressure to atmosphere.
2. Insert test gauge in measurement line. For
liquid filled systems, insert gauge at level of
pressure tap.
Test gauge
F0403.ai
3. Adjust pressure to some value between 0.2 and
1.0 kgf/cm
2
or bar, 20 and 100 kPa, or 3 and
15 psi. Using formula below, calculate output
corresponding to this pressure.
4. Adjust zero elevation or zero suppression screw
so that output is approximately the calculated
value.
Adjust zero screw so that output is exactly at
the calculated value.
If necessary, change zero adjustment on
receiver so that reading is calculated value.
Zero elevation or
zero suppression
screw
Zero screw
With zero elevation
kit, screw is on
opposite side.
F0404.ai
Figure 4.2
Zero Adjustment
Formula to Calculate Output for Transmitter with
0.2-1.0 kgf/cm
2
Output
Output =
(0.8)
Test gauge reading – Lower range limit
+ 0.2
Upper range limit – Lower range limit
Example: Instrument Range, 10-14 kgf/cm
2
Test gauge reading, 11 kgf/cm
2
Output = (0.8)
11 – 10
+ 0.2 = 0.4 kgf/cm
2
14 – 10
Note: With 20 to 100 kPa or 3 to 15 psi output, substitute 20 and
80 or 3 and 12 for 0.2 and 0.8 respectively, in the equation
above.
