670G wants to be calibrated at 2 or 3 or 4AM almost every night

I diligently calibrate my Medtronic 670G EVERY night before I go to bed. My pump keeps waking me up 4 to 5 times a week alerting me that it must be calibrated at 2 or 3 or 4 AM. I ignore it because I want to sleep! It then shuts off automode. (Sometimes it is because my BG is low. In that case I understand why it wants to be calibrated.)
When my BG is 150 in the middle of the night can someone please explain to me the algorithm. WHY does it need to be calibrated in the middle of my sleep? It makes no sense.

When my BG is 150 in middle of night, and I ignore the alert, does the Algorithm keep track of that info and request a BG night after night? The reason I ask this is because I was told by a Medtronic educator that if I do a finger stick during the day and ACCEPT it on my pump the algorithm remembers this and will request a BG at about the same time the next day. Who would write an algorithm like that? She told me to not validate my BG’s unless the pump asks for a BG or calibration. Only exception to the rule is I always validate my BG and calibrate at bed time.

Does anyone else have the middle of the night request for calibration after calibrating before bed? Maybe I need to shut off auto mode for a week and “reset” the algorithm. Any thoughts?

I have had T1D for 54 years and have been on Medtronic pumps for almost 29 years.

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It really does not. Let me explain. The 670g assumes that over time it will have to deliver basel insulin. If it does not do so, it alarms for minimum input and asks for entry to basically say hey you are you still alive?

Now you have three options, ignore the alarm, you cna do this before you go to bed. by using audio options and selecting all alerts and that will stop all alerts except the bottom low. I think it is 60. The down side is this turns off some useful alerts like if you are high.

Second you can as you know calibrate - that starts the clock again for 2.5 hours.

Third you can do what i do. Look at the screen and enter but do not calibrate a BS close to my current BS> So lets sya i am 98 and the pump alarms I am ready for a few Z’s so I will usually enter 100 or 99. Enter but do not calibrate. You get the blue shield back for 2.5 hours, Chances are pretty good if insulin is suspended for 5 hours you will get some basel delivered .

This is how I work with the issue. I hope it might work for you as well.

oh and this is my opinion consult your doctor for help yda yda, yda, yda.

NOTE: I am a Medtronic ambassador. My opinions are my own. They did not pay me to say nice things. OK, they sent me a shirt and a cup but even I am more expensive than that.

Thank you! That makes sense. Appreciate!

As soon as you can, switch to a Tandem t:Slim with Control IQ technology. The software is not as archaic as Medtronic. Further, Tandem is a US Company. Medtronic, according to SEC filings is moving off shore since its purchase of AV Medical.


I do not recall ever getting a calibration request within 2.5 hours. Enter new BG, yes, but not calibrate. However, I often get recalibration requests after six hours during the first 24 hours. Perhaps my recall is not that good.

Don, you are right, I mis-typed. You get the same blood sugar request if after 2.5 hours the the pump is not yet delivering basal insulin.

I think I got it… So if, for what ever reason, no basil delivery has been made in automode within 2.5 hr the pump will request a blood sugar?

When I am requested to enter a new BG in the middle of the night, I usually check the last BG and add a few points (meter readings are usually 5 points over my CGM reading) enter the amount and go back to sleep.

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I’m curious what I’m doing differently.

I calibrate twice a day with my 670G/Guardian. When I do calibrate, the BGM vs CGM is rarely more than 10pt different. Its a rarer occasion to be asked for a calibration other than being prompted to these two.

You are keeping your BGs in a good range. If your BGs are either too high or too low for extended periods of time you will be asked to enter a BG reading just to confirm you are ok.

However, during the first 12 hours may be required to calibrate after 6 hours.

I will resolve to it being that Underarock is keeping in good range. I cant figure it out. My “in- range” is only 78% . I’m taking a break form automode for a week then will try again. Thanks for all the replies.

My in range for 14 days = 78%
Time in AUTO for 14 days = 97%

My in range for 30 days = 77%
Time in AUTO for 30 days = 95%

My target range is set 90-120. High alert at 165, low alert at 80.

My avg A1C over the last two years since going on this system is 6.1
Overall, the 670g system has worked very well for me.

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Wow Looks good!
I checked my target range and my Dr. has me set up on 3
12AM - 6 AM Lo 130 Hi 140 Low alert is 80 and high alert is 225
6 AM - 9 PM Lo 120 Hi 125
9PM - 12 AM Lo 135 Hi 140

Looks like I will need to get his advice on my high alert at 225…It might explain why I get so upset when I go high. Would be nice to avoid that…
Nice to see your settings and compare to mine. Thanks for sharing!

Initially, my trainer set my high alert @+200 (can’t remember exactly what number). The 670G corrects so cautiously when you go high, it seems to take forever to get numbers back under 200. I’ve found, for my purposes, that setting that high alert lower (165 in my case) gives me a chance to “catch” rising blood glucose levels sooner than later. It doesn’t do much for post meal rises, but between meals when they tend to sneak up on me. A manual bolus (in AUTO mode) tends to stop those from ever reaching 200.

I assume you’ve already set the Active Insulin Time to 2 (which is the most aggressive setting you can achieve in AUTO).

Yes, I find it takes forever to get my numbers down. I did adjust my high alert to 185 to see what would happen. Wow! what a difference it made for just a day.

I got used to being frustrated by my bg going high and taking forever to get it back down I didn’t even think about a setting change. So much time feeling blah.
My active insulin time is set at 3. I will probably change and see if that helps too. I’ve heard a lot of people are set at 2. Not sure why my Diabetic Educator and Endo have not suggested that change…I’ll check in with them as necessary.

I appreciate your responses. Feeling better already! Thank you so much!

Glad lowering the high alarm is helping. Like I said earlier, it gives me an earlier warning, thus more time to take corrective measures before I get too high.

The AIT setting to 2.0 made the biggest difference of any setting change I’ve made. Just be careful about making too many changes at once. Try them out for a few days and see how you react. Remember, the 670G is always learning the way you react and adjusts accordingly. Small steps until you get it where you want it.

Not commenting about the 670g, but about diabetes.

High blood sugar is like a giant freight train. Getting a fast rolling train stopped requires more energy and more time to get stopped. I find that that the higher I am, it takes more insulin and I need to allow more time to lower blood sugar even 10 points.

If I am above 200 then it might take 2U to lower it 10 points and under 130, it might actually take less. I have never found it is be same at grossly different levels.

Is this just me?

Gosh the difference is unreal sometimes.

I remember this being explained as result of cells don’t want/need any more glucose, so the insulin “key” has a harder time opening the door, it is double locked!!

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That’s a good point @Rphil2. That’s the same thing I see.

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