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How should I care for my NiMH batteries?
 
NiMH cells are somewhat new to the R/C market. For that reason, we are continually learning more and more about how to charge and care for these batteries. Our current battery care recommendations are to follow. Please check back periodically as we will make changes to this section should we discover better battery care methods.
 
Sub-C NiMH cells that are used on a regular basis are fairly easy to maintain. You only need to discharge them after you run them and put them away. They should be discharged to .9 volts per cell in the pack. So a 6 cell pack will be discharged to 5.4 volts. This can be achieved by monitoring the voltage of the pack as it discharges with a Voltmeter. The pack will not rest at 5.4 volts. When the pack cools it is okay to charge it again. We have found more than 2 charge cycles a day is detrimental to pack performance. The packs can be stored like that if they will be used again in about a week. You only want to charge packs to be stored for a couple minutes (2-5) if they will be stored for 2 or more weeks. It is very important that you discharge them before you charge them back up or they will false peak. Packs that sit for extended periods of time may false peak when they are first used again. This is normal and will happen with all NiMH cells. You can re-peak the pack and use it. The pack will be back to normal after 2-3 charge cycles.
 
If you are using a charger that uses Voltage Threshold to determine the peak of the pack, you should set the Voltage Threshold to 4 mV/cell. The Millennium Pro has NiMH2 charge mode which does not use any type of voltage threshold to determine the peak. It is the best method for peak charging NiMH cells.
 
How should I care for my NiCD batteries?
 
NiCD cells have been around for years and are being phased out slowly due to their harmful effects to the environment. They are relatively easy to care for. After use, they should be discharged to .9 volts per cell (That's 5.4 volts for a 6-cell battery) and stored. They should only be used on time a day for optimum performance and battery pack life.

Why does my Millennium Pro false peak?
 
It is very unlikely that the charger would cause the false peaking issue. Typically the battery pack is the culprit. If the pack is brand new, it will false peak until it has a few good cycles on it. If the pack is very old, or has not been used for a long time, you will see the same problems. See the Battery Care section for more information. If the pack has any loose connections between the cells it may false peak. If the connection between the charger and the pack is not clean, you will see false peaks.
 
What features make the Millennium different than previous Novak Chargers?
 
The Millennium Charger comes equipped with three different charge modes: Reverse Pulse Mode for all NiCD (nickel-cadmium) cells, Linear Mode for NiCD and Sub-C size NiMH (nickel-metal hydride) cells, and NiMH Mode for smaller NiMH cells (AA size transmitter & receiver packs). All three modes are user-adjustable, including the charge rate, delta-peak value (see Peak Detection), reverse pulse duration, and trickle charge rate. The button and alarm tones are also adjustable. The Millennium performs complicated functions and yet it is designed for easy operation and comprehension. The large backlit LCD on the front of the Millennium is electronically adjustable for optimal viewing. An especially convenient feature is that the Millennium displays messages in actual words rather than symbols or abbreviations, which are not always easy to understand.
What is the difference between the RHINO and DIGI-PEAK PLUS Chargers?
 
The DIGI-PEAK PLUS (#4460) has a custom 3.5 digit LCD volt/ampere meter display to monitor the battery pack voltage and charging current. The DIGI-Peak Plus uses Novak's high frequency, 10-bit Digital Peak Detection Circuitry to provide the most accurate charge available. It features two charging modes-- linear and pulse. The Linear Mode is adjustable from 0-5 amps, and is ideal for use with all size SC, SCE or SCRC batteries. The Pulse Mode is adjustable from 0-10 amps, and is ideal for use with all size SCR batteries. The trickle charge is pre-set at 180 milli-amps in the Linear Mode. There is no trickle charge in the Pulse Mode. The DIGI-PEAK PLUS will charge 4-8 cells (1.2 volt nickel-cadmium batteries connected in series).
 
The Rhino (#4470) is a constant current medium frequency entry level pulse charger. The Rhino uses Novak's 10-bit Digital Peak Detection Circuitry, and has adjustable charge current (0.5-10 amps), volt/ammeter jacks, volt/ammeter switch, start/stop button, internal cooling fan and replaceable air filter.

What is PEAK DETECTION?
 
When batteries reach a fully charged condition, the pack's voltage begins to drop. A charger that uses peak-detection senses this drop in voltage and changes from a high rate of charge to a trickle charge (or off in the pulse mode). Digital peak detection is more accurate than analog peak detection.

What is DIGITAL PEAK DETECTION?
 
Digital peak detection measures the battery voltage and stores that information as a digital binary number. This number does not change due to temperature or drift over time. An analog peak circuit stores that same voltage information in a capacitor, which can lose information as time passes (measured in seconds), and is greatly affected by temperature. Digital Peak Detection is the only way to achieve an accurate peak value.

What is the difference between LINEAR and PULSE CHARGING/REVERSE PULSE?
 
In Linear Mode charging, constant current is maintained by varying the applied voltage to the battery to maintain the user-set current value. In the PULSE MODE, voltage applied to the battery is 100% of the source voltage. The user-set current value is obtained by the on/off time of the voltage applied (PWM). For example, if 100% voltage causes 10 amps to flow into the battery, to obtain a 1 amp charge rate, 10% duty cycle is used. This means for any given pulse, the on time is 10% and the off time is 90%.

What is TRICKLE CHARGING?
 
Trickle charging is a reduced rate of charge usually described as the battery capacity divided by 10. This small amount of trickle current allows cells to equalize after their fast charge cycle has been completed. Trickle charging tends to slightly suppress the voltage of the battery pack, and is generally not used for racing.
 

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