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[MVetter]

Diginow stopped selling them because they couldn't get them to work reliably, but it was through no fault of Zero. That they cost as much as a bunch of Deltas is irrelevant because you don't get a bunch of Deltas for free with your bike, it's an additional cost. And no they're not the same size, that's why Diginow also made an extended bellypan to fit them.

Jesus Christ, son. I started to do basic stupid math but then I had to stop because JESUS CHRIST, SON. ahahahahahhahahaha. Let's do some math, shall we, my little stripling? A Delta Q is 900W and costs $600.  And is the size of a pie. Like a large pie. Let's stack Delta Qs together until they're about 10kW. Thankfully that's easy because 11 of them is 9.9kW and would be $6600. Then you'd have to invest in Y adapters to feed into the Aux charging port. My math says that would take .... 12 Y adapters. At what, $250 apiece is an additional $3000.

YEAH BUDDY. That's $9600. But you can't do that because the Aux port has a 100 amp fuse and you will blow it doing this. But  I'm sure you already knew that. Tell me more about how our system works, though.

[Crissa]

YEAH BUDDY. That's $9600. But you can't do that because the Aux port has a 100 amp fuse and you will blow it doing this. But  I'm sure you already knew that. Tell me more about how our system works, though.

Have the snark wires crossed now?

-Crissa

[TheRan]

Diginow stopped selling them because they couldn't get them to work reliably, but it was through no fault of Zero. That they cost as much as a bunch of Deltas is irrelevant because you don't get a bunch of Deltas for free with your bike, it's an additional cost. And no they're not the same size, that's why Diginow also made an extended bellypan to fit them.

Jesus Christ, son. I started to do basic stupid math but then I had to stop because JESUS CHRIST, SON. ahahahahahhahahaha. Let's do some math, shall we, my little stripling? A Delta Q is 900W and costs $600.  And is the size of a pie. Like a large pie. Let's stack Delta Qs together until they're about 10kW. Thankfully that's easy because 11 of them is 9.9kW and would be $6600. Then you'd have to invest in Y adapters to feed into the Aux charging port. My math says that would take .... 12 Y adapters. At what, $250 apiece is an additional $3000.

YEAH BUDDY. That's $9600. But you can't do that because the Aux port has a 100 amp fuse and you will blow it doing this. But  I'm sure you already knew that. Tell me more about how our system works, though.

Don't get pissy with me, I wasn't the one that said they cost the same as a bunch of Deltas. Presumably he was comparing the max allowed Deltas (four, for 4kW) combined with the OBC (for roughly 5.3kW) with the 6.6kW or whatever Diginow. I'm not going to bother double checking the pricing because I wasn't the one that brought it up and because you can't even buy Diginows anymore.

[princec]

These on board charger thingies... they're essentially AC->DC converters yes? I am a little bit surprised that they aren't considerably smaller and more efficient and more reliable than they currently are. This doesn't seem to be cutting-edge electronics. What gives?

Cas

[DonTom]

These on board charger thingies... they're essentially AC->DC converters yes?

No, they are switching power supplies with a very wide voltage range (90 to 250 VAC) with no increase in wattage as the voltage is increased, which is very  tricky to do.

Otherwise, this would happen with a simple AC to DC conversion (such as with a linear power supply):

Zero's 1.3 KW OBC output rated charger, not counting the approximately 10% loss of efficiency to the output DC, with  120 VAC input:

Amps = voltage over resistance.

The  AC input impedance will be  a normal steady value in ohms, so this would happen if used with a linear power supply or even a switched-mode power supply with a design to NOT  reduce  the current as the voltage goes up: 

A. 120 VAC input, 9 ohms impedance= 13.3 amp draw.

B. 240 VAC input , still 9 ohms impedance= so now it's a 26.6 amp draw.

In above:

A.  120 Volts times 13.3 amps=1,596 watts input (1.3 KW DC output, the rest in heat). OBC is happy.

B.  240 Volts times 26.6 amps=6,384 watts (the 1.3 KW output charger would get destroyed instantly). You can change energy, such as power (which is watts) but not reduce it. The extra power (watts)  will be lost  in heat and would normally destroy a 1.3 KW charger with the excessive heat.  The charger  would normally have to be  rated for the much higher power or it would instantly get destroyed.

What the 1.3 KW Zero  chargers (and the DeltaQ Chargers, as well as with the Harley LW)  are designed to do is to reduce the current as the AC voltage is increased by very tricky circuity by  reducing  the time some of the charger  circuits are allowed to work as the voltage is increased. Much more than a simple "AC to DC converter" which would only take a large transformer & rectifier and if done that way would be designed for a very narrow voltage  range, such as perhaps 115 to 122 VAC, which is  not even  close to the wide range of 90 to 250 VAC.

The higher wattage chargers simply allow the power increase with voltage as then the more power is wanted. IOW, you want that 6,384 watts if you have a 6.3 KW charger when you're using a 240 VAC input.

If you look inside the OBC or any EV charger, you will see almost countless components. They are very complicated compared to a " AC->DC converter" which requires very few parts.

-Don-  Auburn, CA

[DonTom]

These on board charger thingies... they're essentially AC->DC converters yes? I am a little bit surprised that they aren't considerably smaller and more efficient and more reliable than they currently are. This doesn't seem to be cutting-edge electronics. What gives?

Cas

One more thing. They ARE very efficient as is. Around 90%.

120 VAC input, 12 amps=1,440 watts AC input.

( or if  240 VAC input with 6.0 amps)

~1.3 KW DC output.

1,300 divided by 1, 400 watts:

Better than 90% efficiency.

To do that in the size and weight of the Zero OBC, and uncooled, I would consider to be very cutting edge technology. IMO, there is not a lot of room for improvement. IMO, only small improvements can be made from here.

-Don-  Auburn, CA

[princec]

Thanks DonTom. I wonder if there might not be some major advances in this particular aspect over the next few years, seeing as they do seem to be a fairly critical aspect for the success of EVs.

Cas

[DonTom]

Thanks DonTom. I wonder if there might not be some major advances in this particular aspect over the next few years, seeing as they do seem to be a fairly critical aspect for the success of EVs.

Cas

I think the rate of improvements will slow down. The 10% loss in heat doesn't leave a lot of room for large improvements. If they are made smaller, then they must be built to dissipate more heat for the size.

The perfect answer is to get as close to 100% efficiently so it won't get as  hot. I just don't see a lot of room to work with there within that 10% loss in heat. 90%  is quite efficient  as is, considering the number of active components inside the charger  that require energy. 

-Don-  Auburn, CA

[TheRan]

A small correction, according to the data sheet it's 92% efficient at 115V, 94% at 220V. That's matched only by the very best 80+ Titanium computer power supplies.

[DonTom]

A small correction, according to the data sheet it's 92% efficient at 115V, 94% at 220V. That's matched only by the very best 80+ Titanium computer power supplies.

Thanks,  that sounds correct. I never looked at the data sheet so I was going with what I would consider to be  close enough for the points I was making.

As you can see, not much room for real  improvements in such a small package.

I normally charge at 240 VAC, so only 6% is wasted in heat. And even that isn't for long as I always connect up a couple of extra chargers.

BTW, I will be off line for several days. I am going backpacking up in the high Sierras for several days and nights. Leaving in about an hour. No cell service up there, I will have satellite communications, but not for the web.

-Don-  Auburn, CA

[Crissa]

Seems like a bad time to be in the mountains, if you ask me,

-Crissa

[DonTom]

Seems like a bad time to be in the mountains, if you ask me,

I ended up in Reno, but for a much different reason than smoke. There was no smoke at all at 7K feet elevation, sky was as blue as can be. Reno is not bad now either. I can clearly see Mt. Rose out my window here,  unlike the last time I was here in Reno where I could not see anything through the smoke.

But I was going the Fordyce Lake area (NW of Soda Springs, CA). I take an unpaved road several miles (in my 4WD Jeep) and there is a sign that the area is closed because of major construction at the dam. It will be completed in year 2023!!!

So I am going to the Island Lake area  to the west, but there will be a two day delay now for me to leave Reno, as I have a few things to do while I am here.

The area I am going backpacking in is right in the middle between my Reno and Auburn house.

I hope nobody minds the thread hijack!

-Don-  Reno, NV

[Crissa]

Naw, hard to see these things as their own threads.  My EV-driving buddy went to Oregon only to be evacuated from the cabin he was renting.  And he went to Oregon to escape the smoke which of there is little escape now.

-Crissa

[Richard230]

My early morning sky is a dark red right now with smoke from fires coming down from Northern California, including fires around Willits (Highway 101 is closed), Oroville, La Porte, Quincy and probably other areas, too. Not a good time to go touring around California. 

I just heard that a number of towns in Central Oregon are on fire and have been essentially destroyed, including Talent, where Brammo used to have their factory.

Here is a photo that I took from my home at 1:30 in the afternoon today.

[DonTom]

In my message 94 above, I just made some minor changes for better accuracy, and a better explanation, in case anybody is interested.

-Don-  Reno, NV