The study objective is to demonstrate that home use of Threshold Suspend (TS) is not associated with glycemic deterioration in pediatric patients with type 1 diabetes, as measured by change in A1C.

This study is a longitudinal, multi-center trial that aims to observe the Threshold Suspend (TS) feature with a sensor-augmented insulin pump in patients 7-15 years with Type 1 diabetes. The study will measure the change in A1C from baseline over a period of one year while subjects are wearing the study pump.

Inclusion Criteria:

1. Subject is age 2 to 15 at time of screening
2. Subject has been diagnosed with type 1 diabetes mellitus and must have been diagnosed for at least one year prior to screening
3. Subject is currently transitioning from pump therapy, with or without continued glucose monitoring (CGM), to the 530G insulin pump system.
4. Subject is willing to perform greater than or equal to 4 finger stick blood glucose measurements daily
5. Subject is willing to perform required sensor calibrations
6. Subject is willing to wear the system (Pump, glucose sensors, meter) continuously throughout the study
7. Subject is willing to upload data every 21 days from the study pump
8. Subject must have Internet access and access to a computer system that meets the requirements for uploading the pumps. This may include use of family or friend's computer system with Internet access.
9. Subject is using either Humalog or Novolog at time of Screening and plans to use either of those insulins throughout the study

Exclusion Criteria:

1. Subject is actively participating in an investigational study (drug or device) wherein he/she is receiving treatment from an investigational study drug or investigational study device.
2. Women of child-bearing potential who have a positive pregnancy test at screening or plan to become pregnant during the course of the study
3. Subject is being treated for hyperthyroidism at time of screening
4. Subject has an abnormality (>1.8mg/dL) in creatinine at time of screening visit
5. Subject has an abnormality (out of reference range) in thyroid-stimulating hormone (TSH) at time of screening visit; If TSH is out of range, Free T3 and Free T4 will be tested; subject may be included with TSH out of range as long as Free T3 and Free T4 are in normal reference range.
6. Subject has taken any oral, injectable, or IV steroids within 8 weeks from time of screening visit, or plans to take any oral, injectable, or IV steroids during the course of the study
7. Subject is currently abusing illicit drugs
8. Subject is currently abusing prescription drugs
9. Subject is currently abusing alcohol
10. Subject is using pramlintide (Symlin) at time of screening
11. Subject has a sickle cell disease, hemoglobinopathy; or has received red blood cell transfusion or erythropoietin within 3 months prior to time of screening
12. Subject plans to receive red blood cell transfusion or erythropoietin over the course of study participation
13. Subject diagnosed with current eating disorder such as anorexia or bulimia
14. Subject has been diagnosed with chronic kidney disease that results in chronic anemia
15. Subject is on dialysis
16. Subject is already on a 530G system with CGM for 8 days or more.