Was holding my pump out straight while it was delivering bolis, when it beeped that it was done, at that same moment, felt pump do like a vibrate/sm. jolt like motion as it finished delivering. Its never done this, as i usually hold pump flat in hand (is this ok, it doesnt matter position of pump/ tubing right, will still deliver right amount of ins and not leak/give more than should?)
Is the jolt/vibration i felt OK?? does thst jolt mean it gave ‘more’ than should/damaged?
Always my biggest fear that pump will give more, bc then you NEVER KNOW HOW MUCH, and coukd be fatal…coukd it just ever give whole pumpful at once? Or lrg fatal amount? Even a drip extra for some is too much…read stories like this 
I can’t tell what you heard or felt, for piece of mind you should call Tandem.
If I couldn’t reach Tandem quickly, I’d reverting to using MDI and BGM testing until I could.
I don’t believe you need to worry about the pump emptying into the infusion set. The way to be sure is to disconnect at the cannula and watch for dripping.
The pump delivers a tiny amount of insulin with each stroke. Many if those strokes are what you feel when you are filling the tubing of the infusion set. The rate at which the tubing fills is the fastest that the pump can work.
So unless the pump continues to vibrate continuously, it can’t be emptying the cartridge in one burst. The piston design makes it unlikely that it can leak out through the tubing, but anything is possible.
If the pump is malfunctioning, then you CANNOT rely on the pump display to tell you how much insulin has been delivered or how much remains. Call Tandem.
Check the pump history, and will show what was delivered.
Options- History- Pump History.
You can review alerts, boluses, etc.
But if you are not comfortable with pump, you can always switch to injections.
(I have used pumps for over 30 years and never had an over-delivery. )
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The pump will vibrate on its last stroke if you have vibrate turned on
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Whats a stroke? And when it beeps that its done delivering, it vobrated as if it was pumping insulin like i feel it sometimes does (is it supposed to do that when delivering?), but have never felt it fo that ehen it beeps/is done, do that made me nervous yhat it wuld give more by accident, and how could you ever tell?
Mine always vibrates when it finishes giving a bolus. Maybe you just never noticed it before?
You could disconnect the tubing at the infusion set and give a tiny bolus (0.1 units?) into the air and wait to see if it vibrates again after delivery, as a test.
A stroke is just a term to describe the pump movement. This pump has an up stroke and a down stroke. The number of strokes translates into how much insulin it delivers.
The vibrator on my pump is very strong. If I have it on a counter when it buzzes, it makes my pump jump
Safety systems are built into the pumps, else FDA wouldn’t approve them. You got me curious now as to how those systems work and are fail proof. Next t-con with Tandem, I’ll ask. I note that the pump never keeps a precise number of units left in the pump, esp when I first fill the pump and tubing. So the pump must compute the number of strokes it takes, to deliver the precise amount of insulin you programmed for a bolus; then it sends an order to the pump to dispense that number of strokes.
Another explanation of Tandem insulin delivery is here.