TrakPower VR-1 Dual Racing Charger - Manual (Page 8)

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ZEROpk to function properly. A lower number means the charger will try to be more precise
in fi nding peak charge, but in certain situations could cause the charger to errantly stop peak
charge too quickly, in which case it may be necessary to increase this number to 8mV or
greater (especially if using an external AC power supply on the input). Press the dial, then
rotate to fi nd the desired peak sensitivity value. Re-press dial to confi rm setting.
D. Peak Delay (NiCd and NiMH batteries only): Sometimes during the early stages of peak
charge a battery’s voltage can be unstable and cause the peak detector to accidentally stop
peak charge. This peak delay feature temporarily de-activates the peak detection circuit at the
beginning of charge to prevent the charger from accidentally shutting down too early. Usually,
a battery’s voltage becomes stable in a very short period of time, whereby the peak detection
circuit can be re-activated. The adjustable range is 1-20 minutes.
E. Trickle (NiCd and NiMH batteries only): This is the amount of trickle charge current which
will be applied to the battery only after fast charge has ended. To adjust, press the dial and
then rotate to fi nd the new current. Re-press the dial to confi rm selection. The range is 0
(off) to 500mA, in 50mA increments. If charging “A” or “AA” size radio batteries (Rx or Tx), it
is not recommended to set the trickle current to larger than 50mA. For Sub-C batteries, the
recommended trickle current setting is roughly C/20 (battery capacity rating divided by 20). If
fast charge is stopped because the battery temperature reached the maximum temperature
setting (see below), trickle charge will not begin until battery temperature drops about 4°F
(2°C) below the maximum temperature setting.
An auto trickle function is also an option. In the auto trickle mode, the charger will automatically
deliver a trickle charge after peak charge ends to help the battery safely reach 100% full
charge. Trickle charge is applied only after an individual peak charge (not after discharge or
cycle), and will remain on until the pack is disconnected. Trickle current is automatically set,
based on the fast charge current setting as listed below:
0.0-0.9A
1.0-1.9A
2.0-2.9A
3.0-3.9A
4.0-4.9A
5.0-5.9A
6.0-6.9A
FAST CHARGE CURRENT TRICKLE CURRENT
0mA
50mA
100mA
150mA
200mA
250mA
300mA
F. Cut-off temperature: VR-1 can monitor the temperature of the battery which is being charged.
This feature is used in conjunction with TrakPower’s optional Temperature Sensor (TKPP5635)
which can be found at local hobby retailers. The Duratrax (DTXP4171), Hobbico (HCAP0281) and
Triton
™ Thermal Probe from Great Planes ® (GPMM3151) are also directly compatible. Monitoring
a battery’s temperature in addition to its voltage can result in most accurate full charges without
damaging the battery, and is highly recommended for use with lithium based batteries. The
adjustable range is from 50 - 176° (10 to 80°C). Each channel has its own designated sensor
jack located on the front of the charger. When properly connected to the jack, the sensor’s white
wire will be on the left and the black wire will be on the right.
i. If it’s NOT desired to measure the temperature of a battery, make sure the temperature
sensor is NOT connected to the charger.
ii. To change the temperature scale from Celsius to Fahrenheit or vice-versa, see the
Confi guration Setup Menu on page 6.
iii. To adjust the temperature setting, press the dial and then rotate to fi nd the new
temperature. Re-press dial to confi rm setting.
iv. The MAXIMUM temperature for lithium batteries varies by cell manufacturer, but as
a general recommendation, the maximum temperature should not exceed 90-95°F
(32-35°C). For lithium batteries, it is better to be safe than sorry! Start with lower
temperatures fi rst and if necessary adjust the temperature setting upward as needed in
small increments and closely monitor the charge progress.
v. During charge, if the battery reaches the selected temperature setting the charge process
will completely stop and will not re-start. Setting the temperature value too low may cause
VR-1 to stop charging the battery before it reaches full charge. In this case, increase the
temperature setting by a small amount, making sure not to allow the battery to overheat
before full charge has been reached. In this case, decrease the temperature setting.