Ultra Low Leakage Medical Power Supplies

Jerome Industries specializes in ultra low leakage power supplies for demanding medical applications. All Jerome switchmode products are designed to be useable in a type B or BF medical application, where the power supply provides the sole isolation barrier. Please note, that in the following table where the power supply leakage current is referred to as "Output", the 60601-1 document refers to this as "Patient" .

For the purposes of leakage current performance analysis, switchmode power products may be divided into four categories as follows:

Design Category
Generalized Description
Normal Condition
Single Fault Condition
60601-1 Compliance Limits:
ALPHA
 This category represents the minimum requirement for safety certification of a power adapter. Only the earth leakage current is taken into account during the design of the power supply. By ignoring other possible useage scenario's, a slightly simpler power supply design is realized.

All Jerome medical grade adapters exceed this category, the basic starting level for all Jerome medical products is the Beta category shown below. 		Earth Leakage: 500uA
(US/UL Deviation limit is 300uA.)		 Earth Leakage: 1000uA
Single fault condition is a open line or neutral connection.
BETA
 All standard Jerome switchmode power adapters meet this category. The output isolation of the adapter will meet the type B and BF leakage current categories from 60601-1. This leakage current data is available on our web spec pages.

Link to standard Jerome Switchmode Products: 		Earth: 500uA
(US/UL Deviation limit is 300uA.)

Output: 100uA		 Earth: 1000uA

Output: 500uA
Worst single fault is open earth connection. (US Deviation under UL specs is 300uA.)

Type BF also requires less than 5000uA leakage with mains voltage applied directly to output.
GAMMA
 Switchmode products designed to this category, will meet the type CF output isolation requirements. To meet this category, it is necessary for us to modify the design and construction of the power supply. The WSL part of our product line has been tested and qualified to these ultra low leakge current requirements.

Link to type CF Jerome Switchmode Products: 		Earth: 500uA
(US/UL Deviation limit is 300uA.)

Output: 10uA		 Earth: 1000uA

Output: 50uA
Worst single fault is open earth connection.

Also requires less than 50uA leakage with mains voltage applied directly to output.
DELTA
 Switchmode products designed to this extra low leakage current category perform extremely well under abnormal situations such as an open ground. The leakage current levels are considerably below CF limits.

Designed for applications where earth grounding may possibly be unavailable or intermittant.		 Note: Delta leakage levels are much lower than 601 CF leakage levels ,
and maintain these very low levels in abnormal situations.
Specified Jerome Performance:
Earth:100uA

Output: 3uA		 Earth: 100uA

Output: 3uA
Open earth, or reversed line and neutral connections.

Also will measure less than 30uA leakage with mains voltage applied directly to output.
EPSILON
 This category represents the lowest level of leakage current switchmode products which Jerome presently produces. The leakage current levels under normal operation are far below the CF limits.

Designed for applications where a reliable earth ground exists in the system deployment environment. 		Note: Epsilon leakage levels under normal operation, are less than 0.5uA
Specified Jerome Performance:
Earth:10uA

Output: 0.5uA		 Earth: 100uA

Output: 15 uA
Open earth, or reversed line and neutral connections.

Also will measure less than 50 uA leakage with mains voltage applied directly to output.

Ultra low leakage current products which meet the Gamma, Delta or Epsilon level leakage current limits, are only available as special order items. Please contact the Jerome sales department at 908-353-5700 with your exact specs in order to determine product line match with your application.

Special non-recurring engineering fees will apply for the Gamma, Delta or Epsilon product families which will generally be divided into: analysis, design, PCB/mechanical design phase, leakage testing, EMC testing, and safety regulatory submission. Delta and Epsilon products will generally have a higher design fee, and lead time than the Gamma products. The Jerome engineering department should be contacted through the sales department, and can give immediate technical support.