User Guide

Figure 2: ICOM D-Star radio equipment.
Figure 3: HPS SR250C 12 TFSL.
Energies also extended the battery
remote temperature sensor cable
to nine metres as the batteries are
located in an outside battery box.
Battery temperature sensor
This is an excellent idea that gives
the SR250C a ‘SMART” control of
the battery. As mentioned above,
the batteries are often at 0C or just
above zero for many days on end
during the winter months.
When ambient air temperatures
are this cold the SR250C charges at
around 14.3 V, dropping to 13.85 V at
18C. The batteries are always charged
to maximum capacity. With normal
fixed output voltage float
chargers’ batteries are always
undercharged when operating at
very low ambient
temperatures.
Battery disconnect feature:
The SR250C has an Electronic
Circuit Breaker (ECB) which protects
the battery circuit against overload
and also incorporates a Low Voltage
Disconnect (LVD) that will discon-
nect the battery at 10.8 V during
a prolonged outage. Based on the
above criteria, after mains fail
the SR250C sends out two signals
‘Mains Fail’ followed by ‘Battery
Low’ alarm (not currently in use)
and finally disconnects the load to
prevent battery damage.
Because this system was so suc-
cessful we requested a quote for a
second SR250C to power the D-STAR
digital radio system, kindly donated
by ICOM Auckland New Zealand.
Helios Power Solutions were
interested to hear ICOM had
given a high level of support to
this new Digital
Smart
Technology for Amateur Ra- dio
(D-STAR). Helios Power
Solutions
then also donated a
SR250C for the ICOM repeater
equipment. Total current with
both VHF and UHF digital
repeaters is 11 amps DC.
Helios Power Solutions SR
models include convenient stepped
feet for side mounting as seen in the
pictures. This made installation
very straight
forward. Crimp
/Solder lugs are also included
in the installation
kit making for
positive connections when using 6
mm to 10 mm cables. Note that
the ‘positive’ terminal is the
common connection with ‘nega-
tive’ used for the separate load and
battery connections.
The pictures show the D-STAR
installation. The SR250C is mounted
behind the Duplexer seen in the
lower front of the cabinet. With two
Helios Power Solutions power
supplies Branch 63 was able to
standardise on battery charging
equipment extend-
ing the life of
the batteries.
Helios Power Solutions are
easy to contact with the on-
line Skype phone available. I used
this a
couple of times to discuss
special options for the Mount
Climie installation. Helios Power
Solutions were
also able to
reprogram the SR250C for our 10.8
V low voltage disconnect,
temperature sensor extension
and 11.6 V low battery warning
alarm modifications. Quick
turna
round time and a very
professional
twenty four month
warranted
product. B
References:
[1] <http://www.heliosps.co.nz/>
[2] < https://zl2vh.org.nz/repeaters/>
[3] <http://icom.co.nz/amateur>
For information on how to get
involved in the new D-STAR Tech-
nology contact Branch 63 Upper
Hutt <http://www.zl2vh.org.nz/> .
BREAK-IN January/February