RTDT285 - RTD Transmitter

Product Diagram

The RTDT285 is a isolating transmitter that accepts inputs from any type of resistance bulb with a signal swing of 7Ω up to 230Ω. In the case of the popular industry standard Pt100 this would represent a temperature span from 15°C up to 650°C.

The RTD is wired in 3-wire fashion to avoid errors caused by lead resistance changes. 2-wire connection can be used with a short lead length or under constant temperature conditions. Lead breakage will cause the output to increase to maximum.

The RTDT285 is linearised to within 0.5% for Pt100 inputs. Differential inputs from 2x Pt100 sensors can only be connected in 2-wire mode. Lead balance errors can be avoided by using approximately even cable run length and same type of cable.

Bipolar temperature differences are calibrated with the 0-point at mid-scale output (12mA).

Final calibration is trimmed using the front accessible zero and span 15-turn trim adjustments and a link selectable output range.

A wide range ac/dc supply powers the input and the output circuit with three way power/input/output isolation.



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

BSI134 Additional Information Required

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.