| MH-C777 FAQ
Detailed Technical Response
Q: I am having
trouble conditioning/discharging my battery pack. The green LED only
shows for a few seconds and then goes back to the charging mode. Is
there something wrong with the charger?
No. This is a very common difficulty. Some
modern battery packs feature a diode protection at the "charging
contacts", the metal contacts usually located at the bottom or back
of the battery pack for drop-in chargers. The diode protection will
prevent the drawing of power and thus hinder the conditioning
sequence. To solve this problem, simply switch to the "radio
contacts" (the metal contacts located usually at the top or front of
the battery pack for radio use). The radio contact can be used for
both charging and discharging.
Q: My battery pack features
more than two sets of contacts. How do I distinguish the positive
from the ground?
First, check the "scale system diagram" at
the back of your manual. It tells you the pin position relative to
the scale behind. If your battery pack is not listed, then some
trial-and-error is required. The best tool to do this is a digital
multimeter. When you get a high, positive voltage, then you have
found the right contacts. However, if you cannot find any
significant voltage, then your battery packs voltage reading is
blocked the one-way diode. The charger, on the other hand, has the
ability to determine contacts, even though your meter cannot read
it. Simply try different combination of contacts on your battery
pack with the charging pins. When the appropriate contacts are
located, the charger would initiate the charging sequence.
Q: The charger seems to
charge in a few minutes, and the initial voltage indication shows a
lower voltage Is something wrong with the charger?
This problem is usually caused by the
battery pack. This situation occurs when your battery pack is
"over-discharged", meaning you have drawn power from the battery
pack too long. To temporarily solve this problem, you can charge
first for about 10 minutes. Then, remove the battery pack and put is
back again. To solve the source of the problem, observe the
following. Most modern radios have low voltage protection. When the
proper indication shows on the radio, remove the battery pack
immediately in order to charge and preserve long life for your
battery pack.
Q: I have a "battery
case" that consists of 4 to 6 rechargeable AA NiCD/NiMH battery
cells. Can I charge via the MH-C777?
Although the MH-C777 is not designed
particularly for charging individual battery cells, this can be
accomplished. First of all, it is recommended that you obtain a
clip-lead, part number MHS-CW4, that can interface with the charger
and your battery case. When charging, make sure all batteries are in
equal state. This means they must be the same model, brand,
capacity, chemistry, and voltage. A mix cell may cause extreme
damage. In addition, in order to prolong the life of your battery
cells, charge batteries from the same electronic device. Another
words, do not mix two batteries from your remote control, another
two from a toy, and another two from your radio. They must be in
equal state. In addition, the conditioning feature is suggested in
this arrangement.
Q: Is there anyway,
using the MH-C777, to analyze the capacity of the battery pack?
Yes! Although the MH-C777 does not feature a
capacity display feature, you can find it mathematically. The
charger's discharge current is about 400mA +/- 50mA. So measure the
discharge current first. Then, count the total hours required to
discharge the battery pack. Finally, multiply that by the initial
charging current. For example, you discharged a battery pack at
400mA for 3 hours. This would indicate a capacity of 1200mA.
Basic Features
Q: The MH-C777 beeps
continuously whenever I insert my battery pack. What should I do?
The continuous beep indicates a reverse
polarity on the charger. Simply flip the "polarity switch" and
reinsert battery pack to reinitialize charging sequence.
Q: What particular
lighting arrangement would indicate a full charge?
When the charge is completed, you will hear
a long beep. In addition, the indicator should only show the
rightmost red LED.
Q: When I discharge
my battery pack, the charger becomes very hot. Is this normal?
Yes. While discharging the internal load is
absorbing all energies and eventually released as heat. Between
discharge / charge cycles, allow sufficient time for cooling.
Q: What is the warranty?
This product is covered by Maha's One Year
Limited Warranty. Click here to read the
details. |