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Pointek CLS 500 – INSTRUCTION MANUAL
7ML19985GG03
mmmm
m
Int
e
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onnect
ion
Communications
Pointek CLS500 is equipped with HART
1
communication protocol
2
so that settings and
values can be obtained and altered locally
3
or remotely.
Diagnostics
The internal diagnostic functions continuously monitor the operation of the transmitter.
An error signal is generated if a failure or irregularity occurs.
Pointek CLS500 sends the signal current according to the NAMUR NE 43
recommendation. During normal operation the current remains within the range from 3.8
to 20.5 mA. If the process exceeds its normal limits but is not in a fault or failure situation,
the signal current will be outside the measurement range (4 to 20 mA) but will be limited
to either 3.8 or 20.5 mA.
If a fault or a failure is detected, the signal current is set to either 3.6 mA or 22 mA,
depending on the settings you have chosen. This feature may be disabled by the user.
1.
Depending on the system design, the power supply may be separate from the
PLC, or it may be part of the PLC.
2.
A 250 Ohm resistor is required only when the PLC is connected to a HART
modem or a HART communicator.
3.
The HART communicator and a PCL/laptop computer cannot both be connected
to the 4-20 mA loop simultaneously.
Typical PLC configuration with HART
power supply
1
R
2
= 250
Pointek
CLS 500
PC/laptop with Simatic PDM or HART communicator
3