Rh eo n i k M esst ech n i k
RE V . L O ct o b er 2014
.
RHEONIK Coriolis Flowmeter
Operation Manual RHE 07, 08, 11
Page
9
NOT E S FO R HI G H T E M P E RAT URE US E (T YP E RHM xx E T 2 u n d 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 indica-
tion.
Fast temperature changes
are generally
not beneficial
for health and lifetime of mechanical
devices.
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 con-
ductor is used for the connection of the RHE terminal nr. 3 (A galvanic separated neutral
point inside the appliance) with the sensor (See the wiring plan attached). All the screen-
ing and single shielded are connected to this electronic terminal.
