Endress+Hauser Turbimax CUE21, Руководство по эксплуатации

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Electrical connection Turbimax CUE21 / CUE22
14 Hauser
5.2 Connecting RS-485 cables
The digital RS-485 half-duplex (2-wire) interface operates with differential levels that are
not susceptible to electrical interference. That is why cable lengths of up to 914 m (3000
ft) can be used. The last device on each bus may require terminating with a 120-ohm
resistor to eliminate signal reflection on the line.
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Do not run the RS-485 cables in the same conduit as the power cable.
If you are using the device in a process control system without galvanically isolated
inputs, you must use a passive barrier e.g. RB223 (see "Accessories") to connect the
CUE21/22.
5.3 Connecting relays
The relays for alarm 1 and alarm 2 are mechanical relays rated at 240 V AC and 2 A.
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Please note that the relays are labeled NO (Normally Open), NC (Normally Closed) and
C (Common).
The alarm relays are configured to be "fail-safe" i.e. under normal operating conditions, the
device is supplied with current and is not in an alarm condition. How these alarm relays
function is described in the "Configuring the alarms" section.
5.4 Connecting the current output
The 4-20 mA output is supplied by a 15 V DC power source and can operate recording
devices with loads of up to 600 Ω. This output is isolated from line power and earth
ground.
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Do not run the analog current cables in the same conduit as the power cable.
How this output works is described in the "Selecting the output" section.
5.5 Ensuring the degree of protection
Only the mechanical and electrical connections which are described in these instructions
and which are necessary for the required, designated use, may be carried out on the device
delivered.
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Exercise care when carrying out the work.
Otherwise, the individual types of protection (Ingress Protection (IP), electrical safety, EMC
interference immunity) agreed for this product can no longer be guaranteed due, for
example, to covers being left off or cable (ends) which are loose or insufficiently secured.
5.6 Post-connection check
Device condition and specifications Notes
Is there any external damage to the device and cables? Visual inspection
Electrical connection Notes
Are the installed cables strain-relieved and not twisted? Visual inspection
Cable run without loops and cross-overs?
Is the cable type run completely isolated at the point of installation? Power cables / signal lines
Are all the screws terminals properly tightened?
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