Multiple chargers on one power point.

Gorgeous Georges

New Member
Region
Europe
Hello everybody.

I'm planning a 2 week tour threw Europe (Belgium Germany Netherlands) with my girlfriend.

She will have two 48v 15ah batteries for her touring bike and I will have a 48v 30ah battery on my cargo bike.
I was wondering if I can charge all 3 batteries on one European power point (230v / 16 amp) at once without overloading it.

I would like to use at least 2amp chargers for the two 15ah batteries and a 4amp charger for the 30ah battery. But I would like to go as high as possible or charge as fast as possible so the more amps per charger the better.

How high can I go? Is it as simple as two 4 amp chargers plus one 8 amp charger which amounts to 16 amps?

Thank you
 
This has nothing to do with ebikes and everything to do with basic electronics.

I wouldn't worry about overloading any wall sockets. Afterall, hotels/motels are made to allow all guests to use their hairdryers, even all at the same time.

Slow charging is best for all batteries. I won't dive into the details why, you can confirm that with the internets.

What's the hurry for fast charging? Plan to ride between 06h00 to 23h59, squeezing some sleep in-between?
 
Hello everybody.

I'm planning a 2 week tour threw Europe (Belgium Germany Netherlands) with my girlfriend.

She will have two 48v 15ah batteries for her touring bike and I will have a 48v 30ah battery on my cargo bike.
I was wondering if I can charge all 3 batteries on one European power point (230v / 16 amp) at once without overloading it.

I would like to use at least 2amp chargers for the two 15ah batteries and a 4amp charger for the 30ah battery. But I would like to go as high as possible or charge as fast as possible so the more amps per charger the better.

How high can I go? Is it as simple as two 4 amp chargers plus one 8 amp charger which amounts to 16 amps?

Thank you
Ohms Law is pathetically simple but I've never mastered it. I think you'll be fine though. The input on 2 amp chargers is typically 1.5 amps for some reason so your two 2 amp chargers and one 4 amp charger will probably use about 6 amps. You could double that on a 120 v 15 amp circuit in the US. I think you could double that again at 240 volts, but hopefully someone who knows will reply.

TT
 
This has nothing to do with ebikes and everything to do with basic electronics.

I wouldn't worry about overloading any wall sockets. Afterall, hotels/motels are made to allow all guests to use their hairdryers, even all at the same time.

Slow charging is best for all batteries. I won't dive into the details why, you can confirm that with the internets.

What's the hurry for fast charging? Plan to ride between 06h00 to 23h59, squeezing some sleep in-between?
True, it has more to do with basic electronics, I just thought maybe someone ran into this problem on an ebike tour already.

I want fast charging because if the batteries are low on the road it would be nice to be able to stop for just an hour and get some actual extra miles out of that charging time.
For this trip I'm not worried about battery health because in the end it will only be about 20 charging cycles.
 
The only reason slow charging is better is because of heat build-up during charging. Heat is the enemy of battery life. As long as the battery isn't getting very warm during charging, you're doing no harm.

Wall outlets? They're all protected from overload, so don't worry about it. And as others have said, you're probably a long way from the maximum anyway, although it's complicated because you don't know what else is on the circuit.
 
A 2A charger will put out about 100 watts (48V x2). The 4A charger will be 200 watts. So your total load is 400W. Call it 500W to account for losses, etc. On 240V, that's 2A, within the capability of a modern hotel. To my regret, I have not been to Europe in 22 years.
 
I can't really foresee any issues....

Worth remembering that sometimes 1 circuit can cover more than 1 room in a building. So the load is shared by all of the available electrical outlets on that circuit, not just the outlet you're using - so you may need to be mindful of others using electrical items. More of a concern in older (domestic) buildings than newer ones... but Europe has plenty of old buildings.

Just slow charge it and get a good 7 hours sleep :D
 
Sounds like a wonderful trip. I spent 3.5 months over two summers traveling through Western Europe in my youth. The first trip was 32 years ago.

Calculating the load is basic math, the difficult part is understanding what is important and what calculations to make.

My charger can output 48 volts at 2 amps. This is 48×2=96 watts. But it does not really matter for your discussion, as this is on the battery side not the input power cord.

My charger consumes 120 watts. The difference in the 120 watt input and the 96 watt output is the inefficiency of the charger, usually seen as heat build up and whatever progress indicators are present. This should be on the label of the charger. You may get lucky and have the input amp requirement documented directly.

My charger will accept voltages from 100 volts to 240 volts. The input voltage is determined by your location. In the US, we have 115 volt nominal (but I have seen it documented as 110 volts or 120 volts), so the charger will consume 120÷115=1.05 amps. In Europe I believe the power is 240 volts, which have the charger consuming 120÷240=0.5 amps.

In either case, the charger power usage is minimal, but you may run into cases where multiple power points in the same room (or nearby rooms) are on the same circuit. It is the combined load on all the power points on a circuit that is important.

Don't go by my word. Do your own research to see what the power standards are, and the various plugs used. My last trip to Europe was long before the EU, and there are some common standards, but you may still run into a legacy system somewhere in your travels.
 
Ok thank you for the helpful replies. I now ordered a 5a charger for my larger battery. It will be at least 31,5ah, I still have to put it together and I have 200 x 3500ah Samsung cells so I might even decide to make it bigger.
I have one 2a charger and one 3a charger for the 15ah batteries. I will test at home to charge them in one socket and see if I can overload it.

Thank you,

See you in Europe ⚡
 
Most chargers are well under 200watts power (more like 150watts). Widgets has done all the maths but basically you are clear to plug lots of them into a wall outlet. Even the 5A charger is only like <300watts so you can plug several in without issue
 
For this trip I'm not worried about battery health because in the end it will only be about 20 charging cycles.
You will want one Grin Satiator for each battery you have to charge at a blazing 8A.

Most stock chargers that come with ebikes are under 4A.

I've done it for about an hour during a lunch and was able to get a battery from 1/6 bars back up to 4/6 bars.

I only do this on the long road. When I am home I do a healthy slow charge of 2A.
 
You're in luck, they made "The Cycle Satiator" just for that :D
Or spend 20 minutes and make your own, just as much more reliable and adjustable for amps and voltage, for a whole lot less. Some of these units have more than one set of outputs.


I love my Satiator but since I charge at multiple locations its crazy to have more than one. These days I only use it on balance charges or charges where I want a charge rate lower than the Mean Wells can go (0.85a, I have the Satiator set to do 0.50a charges).
 
Last edited:
Something else to think about for your trip: On some of my bikes, because these chargers are IP65 rated, they can be mounted permanently on the bike and are fine if exposed to rain or road spray (I do mount them on a plate so there is no direct spray to the cable ingress points). I use the 320w unit, which is good as a 5a charger for my 58.8v 100% charge.

If instead you use the 480w unit, you could wind the thing up to almost 9 amps. That wouldn't be my first choice but its do-able, safely, on batteries as large as what you are describing. Myself personally I'd stick to maybe 8a tops. the pack in my triangle in the pictured bike is a 14S9P, 31ah using Samsung 30Q's.

When charging at these rates, a fanless charger is the way to go as the unit is made to take the generated heat. No fan to fail. And since they are meant for outdoor commercial sign applications, they are meant to last for years. A 157,100 hour Mean Time Between Failure rating. Thats just under 18 years.

IMG_20200410_153001.jpg
IMG_20200412_142152.jpg
 
Just took a trip stateside where I was using a 52V 15amp charger and two 48V 5 amp chargers on the same 120V probably 20 amp circuit. No problems.
 
I like to use a lightweight plastic power strip that has 3-4 plug receptacles and a couple of USB ports. I only need one wall outlet to be able to charge items. It the cord is 1.5 meters in length then it can be plugged into a wall outlet high off the floor and equipment being charged can sit on the floor.
 
Or spend 20 minutes and make your own, just as much more reliable
Oh sure, because that's just so EASY, everyone CAN and SHOULD do it.

We should tell all the LBS's to close up shop as they are obselete, and everyone just DIY their own ebike ground up with mail order ali parts :D

I'm so silly... having 3 Grin Satiators. Was a pain in the butt to move them from room to room.
 
Some stuff to watch out for:
  • A lot of motels/hotels, especially older ones, can have seriously inadequate wiring. So don't just plug stuff in and forget about it -- make sure it is really charging and check on it from time to time. Nothing puts a crimp in your trip like a 30% charge at the start of your day.
  • Generally the best outlets to charge from are the ones with breakers on them in hotel room bathrooms. They seem to be the most reliable and are, in my opinion, the safest.
  • You can also get nailed by inadequate power in campgrounds.
  • Some campgrounds will have outlets available, but they might be turned off at night. So ask and make sure. Again nothing like having 30% charge at the start of your day.
  • USB Power strips are your friend. If you are charging a blinky, a GPS, a phone, and a GoPro they are really the only sane way to go.
 
Back