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CMD
Installation and
Operating Instructions
LEM 300
Double level control unit
for LS 7000 series
©
KROHNE 02/2006 7.02575.21.00
Subject to change without notice.
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Contents
Description....................................................................................................................................3
Product liability and warranty .....................................................................................................3
1
Safety Instructions................................................................................................................. 4
2
Description ............................................................................................................................. 4
3
Technical data ........................................................................................................................ 5
4
Application Example.............................................................................................................. 6
4.1 Example 1 ............................................................................................................................6
4.2 Example 2 ............................................................................................................................7
4.3 Example 3 ............................................................................................................................8
4.4 Example 4 ............................................................................................................................9
4.5 Example 5 ..........................................................................................................................10
If you need to return a device for testing or repair to KROHNE............................................. 11
2 Installation and Operating Instructions LEM 300
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Description
The Double Level Control Unit has two independent, galvanically separated electrical circuits.
Each circuit controls a relay with Normally Open contacts. The status of each relay changes as a
function of the two resistance inputs.
The two inputs act with a hysteresis. The sensibility of the relay circuit can be adjusted from the
front of the module. LED´s indicates an activated relay.
The module can be used as an evaluation module for LS 7000 series sensors. Please refer to the
application example(s).
Product liability and warranty
Responsibility as to suitability and intended use of this instrument rests solely with the operator.
Improper installation and operation of the instrument / system may lead to loss of warranty.
In addition, all claims are subject to the “General terms and conditions of sale” under which this
instrument was purchased.
If a meter or instrument needs to be returned to KROHNE, please note the information given on
the last-but-one page of these Instructions.
KROHNE regrets that it cannot repair or check your instruments unless they are accompanied by
a fully completed Service and Repair sheet.
Installation and Operating Instructions LEM 300 3
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1 Safety Instructions
This instrument is built and tested according to the specifications and packed in technically safe
condition. In order to maintain this condition and to ensure safe operation, the user shall follow the
hints and warnings given in this instruction.
WARNING
During the installation the valid national rules have to be observed.
Ignoring the warnings may lead to severe personal injury or substantial damage
to property.
The product shall be operated by trained staff. Correct and safe operation of this equipment is
dependent on proper transport, storage, installation and operation.
All electrical wiring shall conform to local standards. In order to prevent stray electrical radiation,
we recommend twisted and shielded input cables, as also to keep mains supply cables separated
from the input cables. The connection shall be made according to the connecting diagrams.
2 Description
The Double Level Control Unit has two independent, galvanically separated electrical circuits.
Each circuit controls a relay with Normally Open contacts. The status of each relay changes as a
function of the two resistance inputs.
The two inputs act with a hysteresis. The sensibility of the relay circuit can be adjusted from the
front of the module. LED´s indicates an activated relay.
The module can be used as an evaluation module for LS 7000 series sensors. Please refer to the
application example(s).
4 Installation and Operating Instructions LEM 300