USB charger for TSlim

Hi I am new to Tandem TSlim insulin pump.
Not sure what I am doing wrong but I struggle to plug my usb charger into my pump.
I don’t have a problem charging my iphone but I do every day with my pump.
Is it just me? Is there a trick to line it up?
I miss my Medtronics AA battery.
Any thoughts welcome.

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Have you double checked that the usb charger is facing the right direction to match with your pump? If you look closely you’ll see that the charger and the pump’s port are shaped like trapezoids. You have to orient the trapezoids the right way so that they line up.
Unlike an iPhone where you can just plug it in without thinking about which way it’s connected.

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Edmund @edmundo, keep in mind that your phone probably doesn’t use the same type connector as your t-Slim. Most phones use a “C” formation connector where as the t-Slim has a “micro” port. And as Lise @6yGodsGr reminded you, the upside of the “micro” is a different length than the downside.

You are right, looking closely it is angled in a way that you have to line it up.
Thank you for your response.

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Ditto here. It’s something to do with the port. I’ve had 2 T-slims & first not an issue. This one just difficult. Also had to replace charger 2X. So a minor manufacturing issue I believe but that’ll never hit recall level as still will charge just doesn’t fit as easily as it should. It’s NOT you…


The pump uses an old style trapezoidal USB Mini port. Most non-apple devices use the more modern oval USB C.

Also important to note that the pump is designed to charge at 5 volts and 1 amp, whereas your phone charger is likely 2 or 3 amps and possibly a higher voltage. Charging at the wrong wattage might damage the battery and will almost certainly cause the battery meter to become inaccurate. The latter can usually be fixed by subsequently charging with the charger that came with the pump.

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I’ve problems with this as well. I miss the batteries with Medtronic as well. To me, it’s poor design. The port that receives the usb cord is too small.

There are different types of USB chargers:

T-Slim uses a micro tip. All chargers of the same type are a standard size so any Micro-USB tip should fit your pump. If it is too large flipping it over should do the trick. If that doesn’t work you might be using the wrong type.

I have had no problems charging the pump. And the batteries made the Medtronic heavier, and I had to carry spares in my hand luggage when traveling, which weighted me down. I charge my pump while eating breakfast every day, and no problems lining it up. Look at the opening and the plug and line them up. They are old-fashioned, but they work.