Electrical Connections; Environmental Conditions; Ingress Protection - Mettler Toledo WKC Serie Manual De Usuario

4 Operation

4.1 Electrical Connections

WKC weigh modules have an RS422 interface for the communication with the control systems.
Interface specifications
Interface type
Interface update rate (max.)
Power supply for the weigh module
Input voltage
Input current
Use a stable power supply with no voltage fluctuations.
•
If voltage fluctuations cannot be prevented, use a voltage regulator to deliver a constant voltage value to
•
the load cell.
The power supply must be approved by the respective national test center of the country in which the
•
weigh module will be used.

4.2 Environmental Conditions

WKC weigh modules can be operated within the following environmental conditions:
Temperature Range
Relative air humidity
Height above mean sea level
Warm-up time

4.3 Ingress Protection

IP rating of the WKC weigh modules: IP42
This means, that the weigh module is protected against the ingress of the following:
Solid particles bigger than 1 mm in diameter (most wires, screws, etc.)
•
Dripping water when tilted up to 15°.
•
Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle up to 15°
from its normal position.
4.4 Commissioning
1 Switch on the weigh module at the final location (place of use) only.
2 Observe the warm-up time (at least 30 minutes after power up) before starting with the weighing
operation.
3 When putting the weigh module into operation for the first time, perform an internal adjustment with the
C3 command to adjust the weigh module for the place of use.
WKC
RS422, bidirectional, full duplex, 2'400 to 38'400 bps
RS485, unidirectional, half duplex, 2'400 to 38'400 bps
RS232C, bidirectional, full duplex, 2'400 to 38'400 bps
92 Hz
12 to 24 V DC nominal (10 to 29 V DC)
0.84 A
Operating / Compensated +10 ... +30 °C
Allowable ambient +5 ... +40 °C
Storage temperature –25 °C ... +70 °C
Max. 80 % at 31 °C, decreasing linearly to 50 % at
40 °C, non-condensing
Max. 4'000 m (13'330 ft)
At least 30 minutes after power up
Operation​ ​ 7