H/US/PERAMIC/05-2018/00
Klay Instruments
Page 2/4
WIRING
The figure left shows the wiring connection of the PERAMIC.
The 2-wires must be connected to connectors 3 (-) and 4 (+).
In most circumstances the load should be placed in the negative
side of the 2-wire loop, although this it is not necessary.
TEST FUNCTION
Without interrupting the loop, the actual output (mA) of the transmitter
can be measured by connecting a multimeter to 2 (+) and 3 (-).
The transmitter must always be connected to earth.
The transmitter must be connected with standard two-wire shielded
cable.
Do not
run signal wiring in open trays with power wiring, or
near heavy electrical equipment (Frequency controllers or heavy
pumps). Shielding must always be connected at the side of the power
supply. In case the mounting position is already connected to ground
(by tank or pipe line) do not connect the instrument to ground.
Please
ensure that the instrument is not connected to ground twice to
prevent the occurrence of an Earth loop.
Reversing the polarity will not damage the transmitter, but the
transmitter will not function until the wires are properly connected.
POWER SUPPLY / EXTERNAL LOAD
The minimum power supply is based on the total circuit resistance.
The maximum permissible load (Ri max.) in case of 24 Vdc will be 600
Ohm. By increasing the power supply, the external load can be higher,
till 1200 Ohm / 36 Vdc. (see figure left).
Ri max =
Power Supply
-
13 Vdc
(
min. power supply
)
20 mA
CALIBRATION
All transmitters are fully calibrated at the factory, to customer specified range. When no calibration is requested,
the transmitter will be calibrated at the lowest span. It is advisable to recalibrate the transmitter after shipment.
The calibration sequence is as follows:
1.
The output of the transmitter must be set at 4 mA (Zero-potentiometer).
2.
Air pressure in accordance with the process pressure must be applied to the test nipple.
3.
The output of the transmitter must be set at 20 mA (Span-potentiometer).
4.
Remove the air pressure.
5.
Check if the output of the transmitter is 4 mA. (Otherwise repeat steps 1 till 4)
6.
Install transmitter (See above).
7.
The output must be set at 4 mA (Dependable on mounting position).
COMPOUND RANGE (Combination overpressure and under pressure)
For example: if the transmitter is adjusted at
–1.45 …+1.45 psi the output of the transmitter at atmospheric
pressure must be 12 mA. If not this must be corrected at 12 mA by turning the ZERO potentiometer. After this a
test pressure of 100 mbar should be put on the transmitter and the output should show 20 mA. If not this must
be set at 20 mA by turning the SPAN potentiometer. When the test pressure is removed the transmitter should
show 12 mA at atmospheric pressure. If not the above sequence should repeated.
INSTALLATION
When mounting the PERAMIC, use the same principles as used for manometers (gauge). We recommend
using shut-off valves and water trap pipes according to BS/DIN standards, especially on steam applications
and those applications where the process temperature will be higher than 212°F.
