I bought this nicad battery
cycler just over two years ago, so I suppose I had
better do a review of it. (I can’t keep saying
to the editor that “I’m still testing
it”!!)
I purchased it off 436 Model
shop in New Plymouth. At the time, they were having a
bit of a clearance sale, so I paid $285 for it. They
now retail at $380.
I’ll cheat here and quote
the “blurb” from the advertisement for it
to list the features:
- Two channels operating
independently of one another.
- Each channel can either
Discharge only, Charge only or Cycle nicad
battery packs ranging from 1 to 10 cells in
size and from 100 to 4000 mAH in capacity.
- Two counter displays per
channel. One for minutes and one for
milliamp-hours.
- A bargraph display which
indicates the time remaining for completion
of charge.
- Charger either switches
off or switches to a standby charge after 16
hours of charging.
- Detection and indication
of incorrectly connected battery packs. This
prevents damage to both the Multicycler and
the battery packs.
- Power failure protection.
Operation is suspended during a power
failure, and is restored after power has been
restored.
- The Ktronics Multicycler
can be programmed to cycle any battery pack
up to 10 cells in size (12volts) and 4000 mAH
in capacity on each of its two channels.
I had never bothered with a
nicad cycler before, and had just relied on the good
old charger you get with your Radio-gear to take care
of things. As I had more than one model, I needed
another charger, so at the sale price, I decided to
get this one.
Looking back now, I am
convinced they are “worth their weight in
gold”. I explain:…
We helicopter sorts are always
looking for ways to improve/modify our toys, to
hopefully prevent (or at least reduce to a minimum)
the chance of it plummeting from above. We (should!)
go to great lengths to: reduce vibration (radio gears
biggest killer/enemy), friction, to improve security
of items (loctite, double sided servo tape, rubber
bands, masking tape etc. for keeping it all together)
etc. So, in my mind, the weakest link in the chain is
the possibility of a radio related failure. It is
usually totally catastrophic to say the least, not to
mention dangerous to all nearby.
So, range checking before the
first flight of the day, re-checking
insulation/security of the receiver and
battery/switch connections etc. are just part of the
checks we can do to minimise the risks.
So, I think if there is going
to be a radio failure, it will probably be battery
related.
Which leads me to cyclers.
With the old standard charger,
it was a case of putting the batteries on charge
about 15 hours prior to the next mornings departure,
and hoping for the best. Unfortunately, there are
several areas where you could be let down:
- If your batteries aren’t
nearly totally flat, you’ll be overcharging
them.
- If there is a power cut through the night, how will
you know? (Apart from the microwave blinking at you!)
Who actually checks their TX or RX voltage/output
before the first flight??
- You won’t know if one of the packs has a
faulty cell as there is no way of telling this from
the charger
A cycler does a good job of
warning you of the above events.
After a days flying, I check
the time “on” from my transmitter, and then
discharge both the batteries using the discharge only
function. This tells me very accurately how many
milliamp hours each pack had left. It is very obvious
if one of the packs is dangerously low, and instantly
points to a faulty cell (as a matter of interest, I
also check the receiver pack with a battery checker
that puts a 1 AMP load on it for 10 seconds, straight
after each flight. Some may call me paranoid…).
If the cyclers discharge function is all OK, I know
that I’ve (theoretically) got at least one more
good safe charge left in them for next week.
Also, next Saturday afternoon,
I know the packs are flat and I won’t be
overcharging them. (Some may argue that it’s not
good to leave nicads totally discharged, but for 6
days, I’ve never had a problem yet).
I have not experimented with “peak
detection” chargers though. This Ktronics unit
only does a flat 16hr charge. You can fool it by
telling it that you’re charging a bigger pack,
so you can actually fast charge packs (good for when
the weather has been lousy for the last 6 days, and
fines up Sunday morning after you haven’t
bothered to charge your batteries! However, I would
not recommend fast-charging too often, ‘cause if
you forget about them or muck up your calculations,
you’ll fry them very quickly!).
So, some of the really tricky peak detection tricky
chargers, may be a little kinder to your nicads, as
they are set to turn off immediately they are at
their peak.
Also, this cycler just carries
on as if nothings happened if there is a power cut.
The charging display on this unit is a bar-graph,
each bar represents 1 hours charge to go, so again
it’s obvious if there’s been a problem
through the night.
After 16 hours, I set my cycler
to automatically turn to “trickle” charge
(1/10 normal charge rate) to keep them topped up for
a couple of hours, before I venture out (Auckland
weather quite often dictates a few hours pause
waiting for it to clear!).
As I mentioned this unit can do
2 packs independently at different rates etc. I would
prefer a 4 channel unit, as I have more than one set
of nicads. However, when I want to take two models
out flying, I will cycle one set the day before. As I
have monitored their performance through numerous
charges/discharges, I can be reasonably confident
they’ll hold their (enough) charge for a few
flights the next day. That’s the beauty of it,
it picks up problems before you’d normally
realise.
This review has actually turned
out to be more of a review in general of cyclers and
preventative maintenance, rather than this Ktronics
Multicycler, but I hope it’s impressed upon you,
the necessity of maintaining ALL of your gear, and
minimising risks. This particular cycler is great,
and does everything I want it to do (apart from more
than 2 packs simultaneously) and is really easy to
operate and program.
It has saved me from 1 potential crash -it picked up
a faulty cell which didn’t hold all of it’s
charge properly- so it has well and truly paid for
itself. It is cheap insurance!!
Safe flying…
Northern Helicopter Modellers Club N.Z