KROHNE UFM 500 EN - Manual (Page 8)

8
2.1.2 Connection to power
•
Note information given on the instrument nameplate
(voltage, frequency)!
•
Electrical connection in conformity with VDE 0100
“Regulations governing heavy-current installations
with rated voltages up to 1000V” or equivalent
national standard.
•
Special regulations apply to installation in hazardous
areas. Refer to sect. 6.1 and special “Ex” installation
instructions.
•
The PE protective ground conductor for supply power
⇒
must be connected to the separate U-clamp
terminal in the terminal box of the signal converter
in case of “standard grounding” see sect. 1.3.1,
point 1,
⇒
must not be connected in case of “grounding with
measuring ground M”, see sect. 1.3.2, point 3.
•
Do not cross or loop the cables in the terminal box of
the signal converter. Use separate Pg or NPT screwed
conduit entries for power and output cables.
•
Ensure that the screw thread of the round cover on
the terminal box is well greased at all times.
Connection to power
2.2 Signal converters UFC 400 F and UFC 500 F separate systems
2.2.1 Location
•
Do not expose signal converter to direct sunlight.
Install a sunshade if necessary.
•
Do not expose to intensive vibration
•
Install signal converter as closely as possible to the
primary head.
•
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 routing
•
On normal customer orders, the GK (primary
constant) of the signal converter is factory-
programmed to match that of the primary head with
which it is ordered. The GK is engraved on the
primary head nameplate and also shown on the
converter nameplate. These instruments should be
installed together, otherwise reprogramming of the
converter is required (see sect. 4.3 and 8.2, fct. 3.1.1,
3.1.5 and 3.1.6, only possible with UFC 500 F signal
converter).
•
Electrical connection between primary head and
signal converter by way of factory-supplied sensor
cables MR02 (for single-beam versions) or MR04 (for
double-beam version). Refer to sect. 2.2.3 for the
connection diagrams.
2.2.2 Connection to power
•
Note the information given on the instrument
nameplate on the signal converter (voltage,
frequency)!
•
Electrical connection in conformity with VDE 0100
“Regulations governing heavy-current installations with
rated voltages up to 1000 V” or equivalent national
standard. Refer to sect. 6.1 and special “Ex”
installation instructions.
•
Special regulations apply to installation in hazardous areas.
R efer to sect. 6.1 and special “E x” installation instructions.
•
The PE protective ground conductor for supply power
⇒
must be connected to the separate U -clam p term inal in
the term inal box of the signal converter in the case of
“standard grounding”, see sect. 1.3.1, point 1,
⇒
must not be connected up in the case of “grounding
with measuring ground M”, see sect. 1.3.2, point 3.
•
Line resistance for 24 V DC and 21, 24, 42 and 48 V AC
Max. internal resistance R max of voltage supply
(transformer or DC voltage source and cable)
24 Volt DC / 24 Volt AC: R max 24
≤
1.6 ohms
42 Volt AC: R max 42
≤
2.8 ohms
Maximum length L max of power cable.
L
max
= 28 x A (R max - R
i
)
A C ross-section of pow er cable in m m
2
copper w ire.
R
max
Internal resistance of voltage supply
R
max 24 or R max 42 , see above.
R
i
Internal resistance of transformer or DC
voltage source.
Example:
42 V
AC /A = 1.5 mm
2
/ R i = 0.2 ohm / R max 42 =
2.8
Ω
L max = [28 x 1.5 x (2.8 - 0.2)] = 109.2 m
109.2 m x 3.3 ft/m
≈
360 ft
C on n ection of several sign al con verters to 1 tran sform er
(n = n u m ber of con verters)
Separate pow er cable: R
i increases by factor “n” (R i x n)
Common power cable: L max decreases by factor “n”
(Lmax/n).
> 280 mm (> 11,02")
Power s upply
Outputs
S ens or cable with
Coax ial-entry plugs
(PE = Protective Earth)
(FE = Functional Earth)
Binary Current
output output for
internal
use only