Charge cable tslim

Does anyone use a USB cable to charge their pump ? I have an anker power pack but find the long tandem supplied cable annoying. Itd be great to have a more compact system on the go…

I’ve had the Tslim original pump since 2015 and I’ve never seen a ‘more compact’ charging cable. I just charge my pump while I’m in the shower in the morning. Works for me.

Sure. Doesn’t matter what cable you use. Or what battery. Or what charger.

It all works.

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Thanks for replying…the cable supplied is almost 6ft really gets in the way. I see there’s an adapter thingy on it but guess that’s a power surge protector for wall charging?? I’ll just use the wee cable that came with the anker ( I was nervous I’d blow my pump up !! ).

I plug mine into my laptop when I shower. Works fine.

No. That is not a power surge protector. Nor is any sort of surge protector required for wall charging.

You can really use whatever cable you want and whatever charging adapter or battery.

We will plug it into anything.

Charging it while you shower is quite convenient.

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@Tim35 Out of curiosity, how long does the pump require to fully charge (if you were to recharge once every 24 hours)?

Mine will fully recharge while in the shower. Maybe 10-15 minutes.


Out of curiosity, what is it and what’s its purpose?

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Hence the term… “universal” serial bus… USB

Thanks again everyone, I should have said I’m in NZ with 120v power supply whereas you’re 220v…I’m just nervous of blowing my insurance and having to replace the free one we get. If my pump is down to 40% charged it only takes about 40m to charge.ive decided I’ll use the tandem cable if charging via a wall socket but when using the power bank I’ll just use the anker cable. Everyone’s advice is very much appreciated

USA uses 120v for most typical household appliances and power outlets.

In any event, that has nothing to do with the power coming out of the charger, only the input to the charger. The pump only sees the output.

At the end of the day, you need to do what you are comfortable with.

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I would have to see a picture from the OP to know.

But I would put money that it is a ferrite core designed to suppress noise from the cable so as to reduce interference for other devices.

If so, I would find such a device (ferrite core) on an application such as this (5 volt low amp USB cable) to be entirely pointless. It would take a fairly sophisticated instrument to detect any noise coming from something like that.

I could be wrong. Just a guess.

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This is one of those things that really bugs me so I called Tandem tech support. It’s a small data buffer to guard against transfer interruption during the update process. It has no function during charging but they do recommend using it when updating pump software.

The rep didn’t know what it was at first, but I pressed her to ask someone further up the food chain for an answer.

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lol - Never used that for data uploads either.

I pick which cable to use based on which cable happens to be closest to me when I need one. Assuming it has the correct end connector. Past that - I don’t care.


And regardless of how they described it, if somebody were to cut one in half and post the picture, it would not be surprising if it exactly resembled a ferrite core. Which for the purposes this gets used … really … is useless. But on the other side, doesn’t hurt to use it. Just doesn’t help with anything.

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I think I’ll give Tandem the benefit of the doubt and assume they weren’t blowing smoke with the answer I received. I assume they added it in an abundance of caution to guard against a possible data transfer problem regardless of how remote the chance of that happening may be. It’s a life-sustaining medical device after all.

Bummer… I got the voltages round the wrong way, serves me right for posting on a cellphone:grimacing:

NZ is nominal 240V, same as Australia…

But the voltage at the wall socket is irrelevant, the charge rate can depend on the maximum wattage output of the charger or battery pack. All USB chargers output 5V, but current can vary from 1A to 3A giving a wattage from 5W to 15W. For example, a typical charger that comes with an iPhone is 5W output, whereas the charger that comes with an iPad is 12W. Plug your pump into the iPad charger and it will charge more quickly than on the iPhone charger. The outputs of battery packs vary similarly.

FWIW, most USB chargers these days are built to run on any input voltage from 110 to 250V and maintain the same output wattage.

The answer I was given was that the ‘special’ cable is required only for pump software updates (like the one that will eventually be offered for Control-IQ), not data uploads.
I agree it looks just like a ferrite core, but it’s possible that there is some electronics hidden in there as well.
I stashed mine away in the box in a safe place until software updates arrive, and just use whatever micro-USB cable is closest at the time for charging.

The tandem community page had a section on preferences for charging but it was a bit worrying that its been removed now. But your post absolutely makes sense Dylan so I’m going to hunt out the anker cable and go for it… . .a big thank you for taking the time to post. I’d been too wound up about recharging, I’d forgotten the big picture, selling point, of OS updates.