Hunkin
Garden Products have been selling solar pumps since 1995. Over this
time we have always sold solar brushless pumps as opposed to brushed
pumps. The reason for this is that brushed pumps use tiny brushes
to transfer power to the rotating part (armature) of the electric
motor and are in contact with it, so therefore wear away, causing
pump failure. By contrast, our earlier brushless pumps are still
working after 17 years.
Our pumps did away with the brushes
and had an electronically generated rotating field to make the pump
rotate, but this technology was expensive. However, like all new
technology when it starts to become main-stream, the price drops,
and this has happened with solar pumps and PV panels.
Solar pumps and PV panels (photo voltaic panels,
often just called solar panels) are still a little more expensive
than an equivalent mains powered pump, but with the increased price
of electricity solar pumps can save you money, especially witth
the larger wattage pumps. But the real advantage is the ease of
installation. The moment you decide to use 230 volt mains by law
you must use an electrician to wire up the power supply and that
is when it gets expensive. Mains rated cable buried at least 600mm
underground in conduit and weatherproof power points make it very
expensive. If you have obstacles like paths or driveways between
your power supply and where your water feature is situated it becomes
almost impossible. Solar also fits in well because fortunately when
you need the water the sun is normally shining the most, so the
pumps perform the best.
Solar systems provide a safe, economic alternative to running cable
and they are very simple to install by the home user. Our systems
are designed to just plug together so it could not be simpler. We
use commercial grade solar panels that utilise toughened glass encased
in aluminium frames. You will notice we use larger panels than the
pump wattage would suggest you require. This is what we call "Hunkin
overkill" and we do this because our focus is on performance,
not price. It is a fact that panel outputs drop with temperature
and with age. So a panel in the hot sun, while receiving a lot of
sunlight, also gets hot, which reduces its output. A bit of a catch
22. Panels can also lose up to 20% of their output over time (this
is normal) so having a bit of extra power means the panel will still
be operating your pump in the future. Pumps, like most electric
motors also need more power to initially start, so bigger panels
means earlier starting during the day and continuous operation in
less than ideal conditions.
This says it all from one of our
landscaper customers
"these pumps are great. reliable
and powerful in a small package. I have wasted hundreds of dollars
and time on pumps which are physically much bigger and supposedly
more powerful, but they just dont do what they're supposed to and
are poorly made.thanks again"
All our solar pumps are driven by brushless DC motors.
Our pumps are customised for solar application. Apart from the very
cheap models (under $100) they are primarily designed for industrial
applications, so are of rugged construction. They must always be
immersed in water when operating to lubricate the ceramic bearings
or they will be severely damaged. Warranty is void if the pump is
run without water. This is one reason why we don't like fountains.
Sometimes on a windy day spray from a fountain can fall outside
the pond and the pond can be emptied very quickly.
Our pumps connect directly to the panel, so when
the sun shines (clear blue sky) they pump. When it is cloudy or
raining they don't pump so well. The next question we are often
asked is can we run the pumps on a car battery so it can operate
at night. You can for a very short period (for instance if you have
visitors at night) but a permanent solution is a lot more complicated.
We won't get into too much detail, but basically a car battery is
designed for a short burst of high current to start a car. No battery
likes going flat, and a car battery really doesn't. It can be done,
but it is expensive. For a permanent solution you need deep cycle
batteries, a charge controller and extra panels to run the pump
and charge the battery. Deep cycle batteries alone are $300 plus
each. When you see competitor's pumping system with a 20 watt pump,
a 20 watt panel and a battery, it can't work. If the pump is the
same power as the panel, where does the power come from to charge
the battery?
Installation of our pond pumps is simple:
- Put the pump in the water. (Tip - Place the
pump on a brick so it is not right on the bottom of the pond.
This stops the pump from sucking up all the gunk from the bottom
of the pond.)
- Mount the solar PV panel where it can receive
full sun at midday. Face the panel towards true north at an angle
of approx 40 degrees. The panel produces maximum output when it
is a right angle to the sun because there is no reflection off
the glass.
- Connect the panel to the pump. If the sun is
shining the pump will start either immediately or after a 2 second
delay, depending on the model. All electric motors need a lot
more energy to start than to run, so our larger pumps have a soft
start feature.
Pond pumps, how to select a system
The most important decision is to first work
out how much water you want to circulate and at what height above
the water you want the water to come out.
E.g: You want a waterfall 1 metre high but like
all of us you can't really visualise what amount of water you want
over it to make it look effective. Try this: Fill a bucket with
5 litres of water and pour it over your water feature, timing how
long it takes you to empty the bucket. For instance, if you pour
4 litres of water over your water feature in 30 seconds and it looks
really good then you need a pump that will pump 8 litres per minute
at a 1 metre head. That is 480 litres per hour at a 1 metre head.
Now look at the table below. These are our measured results, not
some manufacturer's theoretical flow rates. ( I am standing on a
ladder or a roof with a 2 litre milk container for some of these
measurements)
|
Litres per hour at height above
water (head) |
Model |
Max flow
|
0.5m
|
1m
|
2m
|
3m
|
4m
|
5m
|
6m |
7m
|
Micro |
240
|
90
|
60
|
|
|
|
|
|
|
DCP-002 |
800
|
700
|
600
|
340
|
180
|
|
|
|
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You can see from the table that the DCP-002 pump
would be for the above example the best pump to use because it can
pump 600 litres per hour at a 1 metre head. Always choose the bigger
pump system because these flow rates are measured under ideal full
summer sun conditions and in reality you will not always get this
result. Pipe work and fittings also contribute to head reduction.
If you have too much water over your feature you can always bleed
off a bit of water into your pond. Too little, can't do anything.
We have applied some "Hunkin overkill" to our panel selections
so the pumps will perform well in less than ideal conditions. Tip:
To make it look like you have a large flow of water going over your
waterfall choose a very flat rock at the top for the water to flow
over. A wide thin sheet of water gives the illusion of a big water
flow when it really isn't.
Solar pump testing to determine pumping
volumes at different heads. Water is pumped into a 2 litre
milk container and the time taken to fill it is recorded,
very technical! From that we calculate the amount of water
at any given head. This way we can be sure that when we
say a pump will pump to a certain height, it will.
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Our pumps are pumps designed for industry and we
have adapted them for home use along with filters. The price list
below is for pump and panel. There is a 1 year warranty on the pumps
and 10 years on the panels. Please
note: None of our pumps are suitable for swimming pools where chlorine
is used. Chlorine is very corrosive and will lead to premature failure
of the pump. Fresh water only. The water must also be clean, so
pumping out of a creek is not recommend.
A common myth
A pump will not fix any algae problems. It is not
the lack of circulation that causes it, it is an in-balance of nutrients
in the water, or too much sun. Too many nutrients is normally caused
by too many fish pooing and weeing in the water. A lot of people
think changing the water will fix it. It won't. It often makes it
worse, because you introduce new nutrients. Sometimes you have to
be patient and let the pond sort itself out. It can take months,
and is more likely to clear up in winter with less sun.
What a pump will do is add extra oxygen to the water
which will support good aerobic bacteria. This bacteria is
everywhere in your pond and they break down all the poo and wee
into nutrients as well as any rotting leaves etc. that have fallen
into the pond. If the pond gets oxygen starved, then anaerobic bad
bacteria thrive, and this is characterised by bad smells.
The only effective artificial method I know of to
get rid of green water is a UV lamp and bio-filter. For that you
need a constant supply of electricity. ie: mains power. However
you are fighting nature and eventually as always, nature wins. Best
to keep a balanced pond.
New for 2015
MICRO PUMP
Our
smallest pump is our little micro that we connect to a 20 watt solar
PV panel via our controller (picture right). By using a 20 watt
panel with our controller this pump will still operate in light
cloud and will run for most of a summer's day.
This pump is so small it is ideal for placing in
shallower ponds. The only catch is you must make sure the pump never
runs dry so the pond must be deep enough to make sure water is always
covering the pump. The pump size is 40mm L x 40mm W x 30mm H. It
can pump a maximum of 240 litres per hour and has a useful head
of about 1m. The outlet is 8mm. The output is adjustable. Fresh
water only. 12 month warranty.
New for 2022
DCP- 002 pump We connect
directly to a 40 watt solar PV panel. A powerful little pump that
pumps a reasonable amount of water to quite a moderate head.
This pump needs at least a 200mm of water depth
and like all the other pumps must not be allowed to run dry. The
pump size with a filter is 110mm L x 60mm W x 70mm H. It can pump
a maximum of 900 litres per hour and has a useful head of about
3m. The outlet is 12-15mm OD, standard garden hose size. Fresh water
only. 12 month warranty.
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