670G & Guardian 3 Calibration: 6hrs or 12hrs?


My replacement transmitter is scheduled to arrive tomorrow morning, according to an email I received this morning. I’ve been searching for other’s reactions to the new hardware but haven’t seen any reports from anyone who has used it. Fingers crossed here. I’ll let you know how it goes.


Same here (I’ve only received a 3-5 weeks notice, but that time should be here soon). I definitely hope that it helps. The last time I changed my sensor, after about 3 days I started receiving a lot of “Sensor Updating” messages. Ironically, the numbers from the sensor (when it wasn’t updating, of course) actually matched even better than usual. Very strange, hopefully the new transmitter will let me have the good numbers without the bad messages.


The new transmitter arrived this morning along with a replacement pump, which I didn’t expect. I’ll give it a try when I have time to set it all up.

I’ve had so many problems lately that when I called Medtronic on Sunday, I told them I was ready to give up on the pump and try something else. That seemed to get their attention. In less than 48 hours, I have the transmitter I’d been wanting and a new pump.

I truly hope it’ll be an improvement. I was happy with the 670g for the first six months I used it, but sensor issues have ruined it for me since last summer.


Wow! That is definitely an interesting story. Even though I would find it hard to believe that saying you were “ready to give up on the pump” would make them send you a new pump, it is very interesting that you received not only your transmitter but a whole new pump almost immediately. The 670G is the one you had before, right (not the 630G or some other version)? I didn’t think it sounded like the new transmitter required a different pump, but I guess if the protocol or software was that different, who knows? I guess we’ll find out when we all get our upgrades…


That’s right–I use a 670g and received a replacement today that’s also a 670g. Fingers crossed.


My Thoughts about the sensor becoming unstable during exercise is that the sensor is moving and must be picking up erratic SG readings from that plus the additional stress on your body. Make sure your sensor is secured good and I would rely on your instinct for lows and check if in question with your meter for highs and lows and just give it time after exercise


I currently have a new transmitter which is meant to stop those BG loops. Check your sensor status if you have version 1.0 call the help line and request the new 2.2 transmitter. Bluetooth is set to start in the near future which will allow Medtronics to update your pumps software


Others discussed some ideas or knowledge. One thing I didn’t see is this. If you calibrate when the body’s real glucose level is rapidly changing, it is almost impossible for the CGM to calibrate, so it will “chase” the glucose level around till it finally gives up and asks for recalibration. I’ve had that happen in as little as about 40 minutes.


I had the Dexcom system for several years. I never had these issues with exercise with the Dexcom G4 and G5 transmitter and sensors. Never. Not once.

If what you are saying is true, then the G3 sensors are useless for people who exercise. And relying on my instinct for high and low makes the whole system worthless.


I have version 2.1 of the transmitter. I requested the updated transmitter several weeks ago. I have not heard a peep from Medtronic. I really don’t care anymore. The system is unusable to me. If I can’t exercise safely with a CGMS then it serves no purpose.


Khurt, All day yesterday I kept getting alerts on low but actually my BG when tested was in the upper 200+ I shut the sensor off as well as auto mode and went to bed. In the morning I turned everything back on and when I tested my BG I was closer but not right on I calibrated and went along my way. I ate breakfast and lunch and got another low SG alert so I checked it and again it was off by allot. The day seemed that when my sensor was goin farther and farther apart even with doing Calibration until I was out of range and got the cannot calibrate notice. I have the 2.2 transmitter so there is still an issue with there sensors. Someday some company will get it right and put all the others out of Business