Casella CEL Automatic weather station - Manual (Page 15)

Direction, Temperature, Humidity, Pressure and Solar radiation sensors for
approximately 30 to 40 hours.
2.7.3 Mains Power Option
Where an automatic weather station system is powered using a local mains
electricity supply, a mains power supply module will be incorporated within the
main enclosure. This power supply generates approximately 18 V DC at a
maximum current rating of 1 A. The input voltage will be provided to suit the
customer’s requirement and is indicated on the unit’s front panel.
WARNING !
The mains power supply adaptor and associated mains input
wiring contain Hazardous voltages.
Always ensure the mains supply has been isolated before
working on the system.
All mains cables and connectors should be protected from
physical damage and water ingress.
A residual current device (RCD) circuit breaker is
recommended at the mains supply input, this will
automatically isolate the system in the event of a fault
condition causing current leakage to ground.
Always ensure metal enclosures are suitably earthed.
The mains supply cable is passed into the enclosure via a cable gland.
WARNING !
Always remove the battery’s protective fuse before connecting
it to the system.
Mains powered systems use a 12 V 7 Ahr battery to maintain full system
operation for approximately 30 to 40 hours in the event of power failure. The
battery is wired to the Sensus logger ‘Battery’ terminals.
2.7.4 Replacement Battery Option
Remotely located systems may be powered by a 100 Ahr sealed and
maintenance free lead acid battery.
This battery is housed within a lockable enclosure at the base of the
frame and must be removed to a suitable mains supply for charging. The
operational time available will depend upon the system’s power requirement and
is influenced by the number and type of sensors and also the communication
method employed. Typically, the battery will power a system having Rainfall,
Wind speed, Direction, Temperature, Humidity, Pressure and Solar radiation
sensors for approximately 5 weeks before replacement with a fully charged
battery is required.
The supplied charger provides intelligent split rate charging. The initial
charge current is 1.5 A but will automatically drop to a low standby value when
90% of the batter’s capacity has been restored. The battery may remain
connected to the charger with no risk of damage. A discharged battery will take
3-4 days to reach a fully charged state.
The battery incorporates a 3.15 A fuse and is connected to the station
system and charger using an ‘XLR’ 3 way connector (pin 1= +12 V, Pin 3= 0 V,
Page 15 of 34
Automatic Weather Station
Assembly & Commissioning Handbook