SI139 - Signal Isolator

Product Diagram

The SI139 converts DC current or volts to DC signals, and features:

  • Input up to 2kVdc and 10Adc.
  • Input options for AC current & voltage up to 500V span and true rms (not sine wave).
  • Input options for bi-polar dc current & voltage.
  • Output up to 18Vdc or 50mAdc.
  • 2000Vrms isolation.
  • Designed for single (factory set) input/output combinations.
  • Front adjustments for span and zero.
  • All common AC or DC supplies.
  • Sensor excitation.
  • Options include adder/subtractor, min/max select, track & hold, peak-hold and ratio adjust.

Common applications include:

  • Signal conversion of DC signals.
  • Prevention of ground and current loops.
  • Protection from dangerous floating voltages.
  • Filter of common mode noise.



Most drawings are supplied in PDF format. Portable Document Format is used to present documents in a manner independent of application software, hardware, and operating systems.


Lead Time for a Traditional Product


Traditional products usually contain the same functionally as standard and premier products but have a different connection, part number or specifications. Traditional products are still available as a service to our customers that have them specified in their plants. Delivery is typically 10 days.

Order Processing


APCS makes and customises products according to a customers order. Upon receipt of the customers order the following information is required before manufacture, allocation or deliver until full details are given, these include;

  1. Identity of purchaser. Company name, ABN (Australian companies), street address and accounts email address.
  2. Required delivery address.
  3. Full part number and calibration detail required to manufacture items.
  4. Total on purchase order to include delivery charges. Orders received with missing information will be entered and marked to indicate missing details and returned to the customer for correction or approval.

Compliance with the above ensures that your items are manufactured and delivered according to the required specifications.

Standard delivery times commence after the order has been approved for processing.