Weidmuller WI-I/O 9-K: Wireless I/O Transmitter v1.9 - Manual (Page 30)

WI-I/O 9-K v1.9
Page 30
is typically 15 to 120 °F (-10 to 50 °C). Special “industrial” batteries, such as Eveready EN91,
have a wider temperature range, -20 to 130 °F (-30 to 55 °C).
Operation of the WI-I/O K will stop during battery change;
however configuration of the module will not be lost when
batteries are removed, so no special procedure is required when
changing batteries of the same type.
Batteries should be inserted as per the drawing - with the WI-BP-
I/O-9-K aligned such that the cable comes out of the top of the
module.
The WI-BP-I/O-9-K can be mounted in any direction. The
enclosure lid can be rotated.
3.4.3 External Battery Supplies
An external battery supply can be used. The self discharge of the battery must be considered, as
often this can be more than the power consumption of the WI-I/O K. For example, most
rechargeable batteries only have a shelf life of 12 months - that is, with nothing connected to
the battery, the battery will self discharge in 12 months.
An example of an external battery supply is two Energizer Alkaline 528 batteries in series. Each
battery is 6V 26 amphour - two in series gives 12V 26 amphour. The combined battery voltage
will drop from 12V to 8V before it is discharged, but this is adequate as the WI-I/O K can accept
supply down to 6V. The shelf life of these batteries is in excess of 5 years and will operate from
0 – 130 °F (-10 to 55 °C).
The use of this type of battery will require an external enclosure, however will provide a much
longer life than the WI-BP-I/O-9-K battery pack. For example, this type of battery supply will
last more than 4 years for a WI-I/O K with an analog input, sampled every 5 minutes for 3
seconds.
The WI-I/O K provides a configurable low voltage alarm for early warning of battery failure. It
should be set above the low voltage limit for the particular battery. For the example discussed,
the low alarm could be set at 8.4V - the battery will still operate for a long period of time after
the alarm is transmitted.
Ensure that the connection between the battery supply and the WI-I/O K is protected by an in-line
fuse rated at no more than 2 amp.
CAUTION!!
LITHIUM Batteries must not be
used when modules are installed
in a hazardous area!