Campbell CS135, User Manual

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CS135 Ceilometer
14
The power cable must not be carrying mains voltage
when it is being connected or disconnected.
4.5.2.1 Power Connections
The following guidance is given to help the wiring and installation of a permanent
power supply to the sensor.
As the sensor is used outside, the installation of the power cables will normally
have to be carried out by a qualified electrician. Please check local safety
regulations.
A mains power source needs to be identified and the type of termination, cable
type and cable run matched to comply with local regulations and the type of
installation.
The power source needs to be able to provide the correct voltage and frequency
and current in excess of the power requirement of the system. See below.
Voltage requirements: 106-137V or 216-253V AC (check power supply
switch and fuses match the nominal 115/230V supply)
Current requirements: 5A
Input frequency: 47-63 Hz.
The power source needs to be fused. The fuse rating should be 5A or larger and a
“slow blow” design. Any extensions to the cable supplied or alternative
replacement should be capable of carrying current in excess of that fuse rating.
The power source should be fitted with a two-pole isolator and should be fitted as
near to the sensor as is possible.
The power cable needs to have three conductors, live, neutral and a protective
earth, normally with IEC wiring colours to match those used.
This equipment requires a protective earth. THIS MUST BE CONNECTED FOR
SAFETY REASONS. Ensure the earth connection at the power source is suitable
for this purpose. The connection should be made via the earth wire of the power
connector/cable or via the earth stud on the sensor base.
This equipment also requires correct connection of the live and neutral conductors
– make sure these are identified and wired correctly at the power source.
Normally, the power source should be fitted with its own or system wide earth
leakage breaker (also known as an RCD).
For short term testing of the sensor a suitable plug can be fitted to the end of the
power cable and the sensor plugged into a standard mains supply capable of
providing 5A at the rated voltage. If this is done the earth wire of the sensor must
be connected to a suitable protective earth point.
WARNING