RHEONIK Messgeräte GmbH
REV. I, Apr. 2004
.
Operation Manual RHE 07, 08, 11
Page
9
NOTES FOR HIGH TEMPERATURE USE
(TYPE RHM xx ET2 und HT)
Installation:
Avoid rapid accelerations or mechanical shocks to the instrument. The instrument should be insulated
in such a manner, that levels of different temperature within the instrument can be avoided.
Heat up / filling with medium:
The instrument should be heated up slowly, so that the temperature difference within the instrument
does not surpass a delta of more than 50°C.
The temperature of the instrument can easily be checked at the RHE.. temperature indication.
Fast temperature changes
are generally
not beneficial
for health and lifetime of mechanical de-
vices.
Attention:
Heavy temperature shocks may damage the instrument. Please do not surpass the limit of
1°C per second
in the case of temperature change.
Example:
medium 350°C - instrument 310°C, - nearly ideal conditions for filling.
Cleaning:
For cleaning purposes temperature shocks should be avoided. Please work within the limits as above
described.
1.3. Wiring sensor RHM
The sensor must be connected to the remote electronic unit RHE with a cable having four pair of
shielded wires plus 1 wire (9 wires).
It is very important that the function groups, drive coils and sense coils are connected separately
(Two single shielded wires for each one – see wiring plan)
In this way any interference between the drive signal and pick-up cables is prevented.
The maximum distance between the sensor and the remote electronic unit is 200 metres, and for the
large sensors RHM 100 and RHM 160 a maximum of 100 metres. In the case of larger distances of up
to 500 metres consult the manufacturer.
It is preferable to use the appropriate measuring cable from RHEONIK. In the case of the laying of
measuring cables, we only recommend cable channels in which no high tension or high voltage cables
have been laid (e.g. for motors).
Avoid connecting wiring points to external systems such as motors or other sources which are subject
to electrical disturbances.
Apart from that, make sure that the main cable shielding or a single shielding can not cause a short
circuit with the sensor housing or any other wiring or components. A conductor is used for the con-
nection of the RHE terminal nr. 3 (A galvanic separated neutral point inside the appliance) with the
sensor (See the wiring plan attached). All the screening and single shielded are connected to this
electronic terminal.
