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Frequently Asked Questions

Nathan Racklyeft edited this page Sep 4, 2016 · 21 revisions

Does Loop require the same pump firmware versions that are needed for OpenAPS-based systems?

Only a subset of older MM pumps support remote insulin dosing commands. For more details see https://github.com/openaps/docs/blob/master/docs/docs/walkthrough/phase-0/hardware.md

Can I open loop, i.e. can I watch recommendations and act on them by hand if I'd like?

Yes. Simply leave the Closed Loop turned off in your settings and you will see recommendations. You can tap the recommendations provided in Loop to enact the recommended temp basal.

Do I need the RileyLink iOS app to run Loop?

No. The functionality needed to communicate with your pump and CGM are embedded in Loop. Only one application can connect to a RileyLink via Bluetooth at one time, so you are better off not running the RileyLink app if you are running Loop; most if not all of the features in the RileyLink app are embedded in Loop so you may only need Loop.

If I am a G5 user, do I need the Dexcom G5 iOS app to run Loop?

You need to make sure that your BG values make it into Apple's HealthKit. Dexcom G5 users will want to run the Dexcom G5 App along with Loop. Turn on Health connection inside the settings of your G5 app. The Dexcom Share approach can be used to get your BG into Nightscout.

What does each of the graphs mean?

  • Blue = your BG values. The background box is your target range.
  • Orange = Net insulin on board (above or below your normal basal rates)
  • Green = Insulin delivery rate as set each 5 minute window. Note, sometimes you may see them bounce slightly above and below zero (on x23 pumps). This has to do with the MySentry readings not having a 1/40 unit precision. Sometimes you may get the same reading in a 5 minute window which implies below or above normal expectation. It's still delivering as per your Basal schedule.
  • Yellow = Carbs on board.

Why do I often see no recommended basal. Is it working?

When Loop calculates a recommended change it will show up in the recommendation row. If you are running a closed loop the recommendation will disappear as soon as it is sent to the pump. So it may only be visible for a minute or two.

What is sensor state?

This is the state of your CGM sensor (Dexcom). For Loop versions 0.9 or older, these are listed in code format. In versions 0.10 or newer the state is self explanatory. This Q/A should be removed once we are to version 0.12 or so. Those 0.9 and older codes are as follows:

  • 01 - Change sensor now
  • 02 - In 2 hour warmup
  • 04 - Enter BG Now after a warmup
  • 06 - All is well
  • 07 - Calibration requested

Why does Loop sometimes pop up the bolus screen after entering carbs, but other times it does not?

For safety reasons, if your BG is predicted to be below the target glucose range you've specified it will not recommend that you bolus.

Does Loop pull or use settings (basal profile, ISF, insulin-to-carb ratios) from the pump?

Loop does not currently (8/24/2016) pull your pump's basal profile, ISF, or insulin to carb ratios from the pump. Therefore, users should make sure pump settings match the settings entered in Loop.

What is Amplitude? How can I find out more?

It is a mobile analytics solution (amplitude.com) that some users have used to track things like how often the loop completes successfully, how often reservoir and battery changes occur, how often the app is launched, and more. This is not required unless you'd like to keep track of that type of data.

Do I need to pay for an account with the Apple Developer program to build and run Loop?

No. You can install apps you build on your own device without a paid account. However, if you do not have a paid Apple Developer account ($99/year) the provisioning on your app will only last for 7 days, and you will have to rebuild and reinstall it weekly. (This appears not to be documented officially, but has been widely reported anecdotally, e.g. here.)

My pump is having trouble receiving temp basal from Loop.

  1. You must use Insulin Rate (not % of Basal) in order to be able to Loop. To set this on your MM pump, go to Basal -> Basal Setup -> Temp Basal Type -> Insulin Rate (U/H)
  2. Make sure your pump is not suspended.
  3. Make sure you are not in the middle of a Square or Dual Wave bolus that you have entered manually into your pump.
  4. Check your battery. If it is showing 25% or less you may want to try a new one. Intermittent comms issues may be preventing the temp basal from being set.

Does loop work in mmoL as well as mg/dl?

Loop uses your preferred unit as set up in Apple Health. Open the Health app on your iOS device. Find Blood Glucose, then unit. You can switch this to your preference (regardless of the format used by the device that is sending BG to your phone). Once that is done make sure to have your Loop Target Range set to your targets in mmoL. If you were previously using mg/dl, go into Target Range under your Settings (in Loop) and delete them. Go out and then back in again and it will allow you to add your ranges as mmoL.

My Loop is reporting that it hasn't run in a while what could be wrong?

There are a number of common things you can do to troubleshoot your issue take a look at some of the common troubleshooting paths below.

1. Bluetooth Communications Issues

Bluetooth issues are pretty hard to recognize as the application will look like it's working properly. One way of testing is to use the RileyLink Configuration and Run a Tune.

[Loop App] > [Settings] > Devices > [RileyLink] > Commands > [9xx.xx Mhz / Tune] >..

If this is successful run "Get Pump Model" as well. If you are having communications issues you can always reset Bluetooth on your iPhone.

[Settings] > [Bluetooth]> [On/Off Toggle]

2. CGM Data Issues

It's pretty easy to see if you are having issues reading your CGM data when using Dexcom G5. The Latest CGM will tell you the last time it was read from the CGM. The Dexcom G5 broadcasts every 5 minutes so if the date and time is older than 5 minutes you may be having communications issues with the G5. Open the Dexcom App and take a look. A Bluetooth reset can help here too..

[Settings] > [Bluetooth]> [On/Off Toggle]

3. General App Issue

Sometimes the Loop App has an internal issue, and you may need to reset the App. To do so just Kill the App by double pressing the [Home] Button and swiping [Up] on the Loop App. Relaunch the Loop App and open the RileyLink Settings and Run Tune.

[Loop App] > [Settings] > Devices > [RileyLink] > Commands > [9xx.xx Mhz or Tune] > ..

It can take up to 11 minutes for Loop to collect both CGM and Pump Data needed to properly recommend temp basals and start "Looping". Be Patient.

4. RileyLink not responding

If you've reset Bluetooth and the Loop App and still are having issues communicating with the pump you can power reset the RileyLink. There is a small switch next to the power charging port. This will shut off the RileyLink. Turn the RileyLink off then back on to reset it. Typically you will see solid Blue LED's that don't turn off if the RileyLink is not responding (more info on RileyLink lights). If you reset the RileyLink be sure to run a Pump Tune when it is back on to initiate communications.

[Loop App] > [Settings] > Devices > [RileyLink] > Commands > [9xx.xx Mhz or Tune] > ..

5. Battery voltage low

Looping uses batteries (especially in older x22 pumps). This is because we are asking the pump to use it's radio in a way that it was not originally intended. That's ok, we just need to be mindful of the batteries. If you are continually getting communications timeouts when running Commands from RileyLink, try and remember the last time you changed the battery in the pump. Most users have found on x22 pumps a Lithium battery will last about 7 days. After that it's hit or miss. The pump screen will show that the battery is full but it will not be able to use it's radio. Swap out the pump battery and run a RileyLink Tune..

[Loop App] > [Settings] > Devices > [RileyLink] > Commands > [9xx.xx Mhz or Tune] > ..

Extra Loop UI Features

If you click on the charts you can drill down to more detail.

Examples: Tap on BG opens Dexcom app, Tap on COB to edit past carb entries

Carb entries can be edited.

Decided to eat at a different time than you thought when you pre-entered your carbs (as a pre-bolus)? You can change the time, amount and even absorption time after the fact.

Bolus Failure Notification Retry

If you receive a Bolus failure as an iOS push notification you can swipe the notification to retry your bolus right from the notification screen.

Recommended Basal Enact

You can press on a recommended basal to enact it immediately. Helpful if you are open looping.

Have more than one RileyLink?

You can go in and edit the name of your RL by clicking on the name. Be sure to wait ~5 seconds after setting and saving for it to take effect.

Enter Carbs and Bolus on Apple Watch

A force touch on the BG screen on your Apple Watch will allow you to enter a bolus or carbs from your wrist.

Carb Entry from other Apps

Carbs are read/write from Carbs in HealthKit. You can use a different app such as myfitnesspal to enter your meals and carbs. They will carry over into Loop automagically. Note, if using a 3rd party to write carbs you will not be able to edit them from within Loop to make subsequent edits.

#Safety Tips for Using Loop

Empty Reservoir

Loop will always attempt to calculate Insulin Effect and IOB (insulin-on-board) from the pump's reservoir units remaining. If the reservoir data is sparse, or if the reservoir reaches 0, it will fall back to using the pump's event history. It is still recommended that you change your insulin cartridges on or before reaching 0 units.

Bolusing and Priming

Primes are differentiated from boluses by the speed of reservoir drop (>6.5 U/hour). For additional safety, pump event history is used for Insulin Effect and IOB calculation for a period of time (the Insulin Action Duration) after a rewind. If after that time any primes are visualized as boluses, reservoir entries (pre-prime) can be deleted by tapping Edit or swiping left in the Insulin History table.

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