GT500 Introduction

[Howard Matos]

[AzHeliCrasher]

Anyone have one yet?

[Gregor99]

Originally Posted by AzHeliCrasher

Anyone have one yet?

There are some GT500 owners in this thread starting on page 3.

http://www.rcgroups.com/forums/showt...2413184&page=3

I've been using one since the start of the GT500 beta 5 months ago. Here are a few pros and cons from my perspective.


Power - The 500 limit is less of an issue than it first appears. With a single GT500 you can parallel charge a 12s 3300mah pack at over 3c. A 12s 4400 pack can be charged (in parallel at just over 2c). With 2 GT500s you can come close to maxing out a Honda EU2000. I can explain this if anyone is interested.

UI - The navigation wheel and larger display are a welcome change from the old style 4 button/2 line display that has dominated the charger market for decades. While the display as not color, it's a lot easier to read than some of the other displays on the market than pack a ton of info onto a tiny screen.

Parallel Charging - If you are familiar with the parallel charging feature on the Powerlabs, you will miss not having it on the GT500. The Powerlabs remain the tool of choice for users that want or need all the advanced capabilities found in the Powerlab series and charge control software. While you can still parallel charge with the GT500, you will need to manually multiply charge current times the number of packs, and manually divide mah put back in. Of course reported IR values also need to multiplied times the number of packs in parallel.

Input Voltage - A lot chargers in this market segment only accept 18v max. At 12v you won't be able to reach the maximum wattage rating on the charger. The GT500 supports up to 30v. But can max out the charger on most charging scenarios with 24v.

USB Interface - The USB interface on the GT500 is included in the charger and you are not required to purchase a separate item. The PC software can be used for firmware updates and charge cycle monitoring. It does not have graphing like the Powerlabs, nor can you configure presets, or charger settings through the software.

Power Supply Presets - The GT500 has 6 power supply presets, for users that regularly swap between different power sources. Handy if you use a deep cycle battery at the field and DC power source at home. Regenerative discharge is automatically enabled for deep cycle power source presets and disable for power supplies. The supply menu can be configured to popup at every power on, or you can turn off the menu and have it default to a specific preset. There are six presets pre-defined, but all six can be tuned, changed, or renamed.

Charge Cycle Presets - The GT500 does have 28 presets. Unlike the Powerlab series the presets are not populated at the factory. To populate a preset, you can go through the normal charge cycle startup, set current, chemistry, CV termination, etc. Then select "Save". It will take you to the preset screen where you can name it and select the slot to save it. The charger will remember if you normally start your charges from the preset menu, or the main menu and take you there the next time the charger powers up.

True float mode for Lead Acid - After the lead acid charge cycle has finished, the charger switches to a float mode which uses a constant voltage setting (CV) instead of the more commonly used constant current trickle mode. The float mode (CV) is recommended by battery manufactures and better for the battery.

[Mateyhv]

Originally Posted by Gregor99

...True float mode for Lead Acid - After the lead acid charge cycle has finished, the charger switches to a float mode which uses a constant voltage setting (CV) instead of the more commonly used constant current trickle mode. The float mode (CV) is recommended by battery manufactures and better for the battery.

Isn't float mode present in Powerlab 8?

[Gregor99]

Originally Posted by Mateyhv

Isn't float mode present in Powerlab 8?

In the Powerlab, its a trickle mode that uses a constant current profile and is disabled Powerlabs lead acid preset.

[MotorG525]

How fast can this charge a 7s 5000?

[Gregor99]

Originally Posted by MotorG525

How fast can this charge a 7s 5000?

Its 500 watts so that works out to be roughly a charge rate of 3.4c.

[Mateyhv]

Originally Posted by Gregor99

In the Powerlab, its a trickle mode that uses a constant current profile and is disabled Powerlabs lead acid preset.

Thanks Greg, the new IU and the navigation wheel look appealing. And thanks for the review!

[MotorG525]

Is this physically smaller then a PowerLab 6/8?

[Gregor99]

Originally Posted by MotorG525

Is this physically smaller then a PowerLab 6/8?

Same size as the Powerlab6. It also has the same interlocking case design on the Powerlabs, so you can connect to 2 together.

[prokyon]

Does the fan stay on all the time at constant speed while charging or can it tone itself down like the iCharger?

[RevoFong]

Hi,
The fan stays on during every charge or discharge and remains on for another two minutes after that to further cool the components in the charger.

[cycled]

I have the GT EIGHT (800W/30A version). It can charge four 5Ah 6s lipos at 1.5C and balances very quickly (compared to my iCharger 106b clone). It's pretty easy to use, though some slight delays when starting charging etc. It's huge compared to the 106b. My only regret really is that I didn't get the GT 500 duo instead to be able to balance more packs independently.

[Jasons9]

I'm trying to recover a couple of packs and get a more accurate charge from my GT500.

Under the advanced lipo charge menu I've changed:

-C/? Termination to (C/20)
-Req Balance Done to (YES)

Are these the best setting to get more accurate balance of the cells?

[RevoFong]

Originally Posted by Jasons9

I'm trying to recover a couple of packs and get a more accurate charge from my GT500.

Under the advanced lipo charge menu I've changed:

-C/? Termination to (C/20)
-Req Balance Done to (YES)

Are these the best setting to get more accurate balance of the cells?

The C/? Termination have a greater effect in bringing the cells closer to the set voltage instead of a more accurate balance. You should also increase the CV timeout in case the cells take a long time to balance.