KROHNE VFM 1091 - Manual (Page 7)

7
Location
•
Do not expose the compact flowmeter to direct sunlight Install a
sunshade if necessary.
•
Do not expose to intense vibration. If necessary support the pipeline
to the left right of the flowmeter.
•
The rotating design of the housing makes it easier to connect the two
cables for power and outputs to the terminals in the rear terminal
box.
Cable diameter
•
To conform to protection category requirements, observe
•
the following recommendations :
•
Cable diameter: 8 to 13 mm (0.31" to 0.51")
•
Enlarge the inside diameter of the Screwed conduit entry by
removing the appropriate onion ring(s) from the seal, only if cables
have extremely tight fit.
•
Fit blanking plug PG16 and apply sealant to unused cable entries.
•
Do not kink cables at conduit entries
•
Provide water drip point (U bend in cable).
Conduit Installation, general wiring considerations
When electrical codes require conduit, it must be installed in such a
manner that the meter connection compartment remains at all dry
times.
•
In case of functional extra low voltages (24VDC) protective
separation in conformity with VDE 400 part 410, or equivalent
national standard, must be ensured.
•
Hazardous area application will require the connection of
protective Earth.
•
Connection to power, VFM 1091 K
•
Current and frequency outputs are galvanically isolated when the
optional ground above is not used and can therefore be
simultaneously connected to a receiver instrument which is
grounded or separately connected to two receiver instruments.
•
Ensure that 24V, 4-20 mA loop is grounded at one point only (i.e.
either at the input of the signal converter or at the input of the
indicator, or at the output of the Power Supply). Do not ground the
loop at more than one point.
3. Electrical Connection
3.1 Installation Location & Cable diameter
3.2 Connection to loop power supply
3.3.l Abbreviations
Abbreviation Stands for
Programming
via Fct. No.... Description
see Sect....
Electronic counter
Electro-mechanical counter
Pulse output
Pulses for Q =100% flow rate
0% flow rate
Full-scale range, 100%. flow rate.
EC
EMC
P
P
Q
Q
100%
0%
100%
-
-
1.3.X
1.3.2
1.1.2
1.1.2+1.3.2
3.2+3.3.4
3.2
6.1+6.2.9
6.2.9
6.1
6.1+6.2.9
• The current output is galvanically isolated from Pulse output P.
• Max. load at terminals 5/6
3.3 Outputs
3.3.2 Current (analog) output I
max. load in Kohms
U – 12 V
B R =
B
< 1200 ohms
20mA