Tuesday, July 17, 2012

BlitzRCWorks G4 Quad Charger / Thunder T6 Multi Charger

BlitzRCWorks G4 Quad Charger / Thunder T6 Multi Charger

Update:  My Common Sense RC 250W PSU has two sets of outputs (see photo below).  The set I had hooked up died cold after only a week or two of moderate use.    I am currently running on the second set with low expectations.  Avoid. 

Note: The defective Common Sense RC PSU is not related to the BlitzRCWorks G4 Quad Charger itself.


Back in January, I reviewed two inexpensive, expensive battery chargers.   I guess that means medium priced.

Quick update:  The Onyx became unusable, routinely beeping to a halt with a "Balance Error" regardless of the battery's actual condition.  I've moved it to AVOID.

This charger is more in the expensive class, closer to a power-user option:  the BlitzRCWorks G4 / Thunder T6 (from
bananahobby.com/hobbypartz.com respectively).  There are a few misc differences between distributors, so look at the pics and video provided by all of them very carefully.  For example, the G4 and T6 differ in the amount of heat-sink built-into the front and back edge of the case, the G4 apparently has a deeper sink.  Also, the G4 has JST format balance lead connectors, while the T6 uses open pins which is more flexible but can be hooked up improperly.  The basic charger is probably sold under a few other names on other websites, so shop around and shop careful. 

I'll just call it the G4 from here.

SPECS
- Input Voltage Range: DC 12 - 15 Volts
- Power Supply Unit: Not included
- Total charging power: 200W (50W each channel)
- Max Discharge Power 20W (5W each channel)
- Max charge current: 20A (5A each channel)
- LiPo or Li-ion Cell Count: 1-15 cells
- Pb Battery Voltage: 2 – 20V

FEATURES
- Four, independent battery chargers
- Modes: Charge, Balance Charge, Fast Charge
- Solid aluminum casing with integral heat-sink
- Includes Deans connectors and a balancer variety pack
- Safety:
-- Delta-peak sensitivity
-- Capacity limit
-- Temperature limit
-- Processing time limit
-- Input power monitor w/programmable voltage shutdown
-- Automatic cooling fan

Although the G4 only costs about $80 (or $64 after the coupon codes posted on this site), the price is a little deceiving because it does not come with a power supply.  That's actually ok if you don't mind using a car-battery; it can hook up to a 12-15V source right out of the box .

For those of us that want to charge without a hood ornament poking our ribs, you'll need to add a AC-->DC Power Supply Unit.  A good PSU will add another $40 or so, about $120 with plenty of juice to overcome transfer inefficiencies, look for at least a 240 Watt unit to power the G4 at full bore.


Hobbypartz 14V,
350W PSU
($40)

Common Sense RC's 15V,
250W PSU
($80)

If you are good with computers and a soldering iron, you can convert a 250W+ ATX PSU as a moderate soldering project, but to me the price difference isn't worth the hassle.

You'll also need to add maybe $30-50 in balance boards and/or connectors to suit your preferred battery style.  So all told, this thing will run you about $150 fully functional.  $150??  For that you can buy 2.5 of the excellent little Dynamite Passports--the model that won the January H2H.  True.  But the G4 can do more than 4x the work of one Passport.

The G4 has four, fully independent charging channels, each providing up to 50W of charging power (the same as a Dynamite Passport's single channel), or 200W simultaneously.

Ok, so this time, in English.  The G4 can fully charge:

- Four, 4400 mAh 6S batteries in 1 hour, 50 minutes
- Four, 3000 mAh 4S batteries in 48 minutes
- Four, 2200 mAh 4S batteries in 36 minutes

- Four, 2200 mAh 3S batteries in 27 minutes

A rare glimpse inside the Z8RC hardened steel
charging vault, where several hundred LiPo batteries dwell in cold,
fireproof isolation from the rest of God's Universe

That's what is advertised.  In reality the G4 performs a little better, peaking close to 55W per channel.  It might help that I bought a 15 Volt, 16.5 Amp, 250 Watt, PSU.  The higher voltage should provide a little more efficient power transfer.

Even cooler, you can charge some combination of the above at the same time.  And if you have several copies of the same type of battery, you can add a parallel-capable balance board to one or all of the four channels for about $10/each. 

PB-XH-EC5

Two boards similar to this one are shown on the second shelf of the charging vault, in the photo above

With a balance board like that, you can charge up to six (similar type and capacity) batteries on each of the four channels.  So using bullet #3 above as an example, you could charge six 2200 mAh 3S batteries in 2 hours, 40 minutes only using one of you four available 50W channels.

That's a whole lotta charging for $150 if you ask me.

True, there are faster individual channel chargers that could get you back into the air quicker from underneath the hood of your car.  With only 50W available to any single battery, field charging is probably not the G4's forte.  The G4 provides great value when charging in quantity.

The G4 also has a ton of safety features and mid course checks, to help keep the Fire Dept away.  Two of the four channels have temperature sensor sockets associated with them, with a programmable temperature stop if a battery begins to get warm.  The charger also checks the cell count before starting, so it won't let you select the wrong voltage.  It lets you set separate clock time and battery capacity timeouts, and it halts current in the event of any line break.

The hobbypartz video series does a nice job walking through some of the menus:

Better still, the G4's digital menu system is almost as convenient as the Passport's hassle free plug-n-charge operation.

The G4's build quality is heavy, industrial grade; really nice. The CSRC 250W PSU sports a similar heavy aluminum nearly matching case, and both have integral heat-sinks running around the perimeter.

The menu system, while still susceptible to an illogical quirk or two, is a breath of fresh air compared to Duratrax Oynx and is mostly straightforward. 

As nice as the charger is, the G4 will appeal primarily to the charging demographic that prefers to haul a lot of batteries to the strip rather than recharge one or two in the field.  Or, to those who have a wide variety of battery types to reload.  I’m in both of those camps, so I really like the idea of getting four fully independent channels that charge in parallel, even each only churns at an average pace.

For someone like a focused T-Rex 600 flier on a budget, who needs to recharge one 6-cell 5000 mAh LiPo battery as fast as possible in the field, this is certainly not the fastest charger for the money.

Issues?

Mostly nitpicks:

- It would be nice if the G4 remembered your last charging mode after a restart instead of needing to put all four channels back into Balance mode.
- It is unclear what the “LiPo Charge” mode does, as opposed to the “LiPo Balance” mode.  Both modes require a balance connector hooked up in order to operate.
- Pressing the “Start” button to change the flashing input field is not intuitive.  You have to press and hold “Start” to actually start.
- After pressing and holding “Start” the charger auto detects the cell count, shows the user-selected cell count vs the auto detected cell count, and then asks you to confirm a start.  To save an additional button press to start every charge, why not ask for confirmation only when the user-selected number of cells does not match the number of cells detected?

Overall, it's great to see a reasonably streamlined, menu-driven charging experience with plenty of power to reboot the airplane collection. 

Highly recommended.

Overall:  A-
Fast if you have a lot of batteries to charge in parallel.  Needs pricey PSU.  Good safety checks.  Great configurability and charging power for the $.