RTD measurement

Basically the electrical resistance measurement range is independent adjustable of the RTD transformation. Thus achievable temperature measuring accuracy depending on the electrical resistance measuring ranges are given in the following. When choosing the combination, make sure that the correct and sufficient electrical resistance measurement range depending on application selection is made, e.g. would be the 50 Ω range in combination with a PT1000 sensor rarely useful only. So a setting have to be chosen for

• electrical resistance measurement range in [Ω] within CoE 0x80n0:01
• the transformation/conversion R → Ω within CoE 0x80n0:14

RTD measuring range

In temperature mode, only the legacy range is available, the extended range is not available.

The temperature display in [°C/digit] (e.g. 0.1°/digit or 0.01°/digit) is independent from the electrical measurement. It is “just” a display setting and results from the PDO setting, see chapter "Comissioning".

Implemented characteristics, overview

Supported RTD types and transformations supported by the ELM370x from FW01 on:

• None (no transformation)
• PT100 (-200...850°C)
• PT200 (-200...850°C)
• PT500 (-200...850°C)
• PT1000 (-200...850°C)
• NI100 (-60...250°C)
• NI120 (-60...320°C)
• NI1000 (-60...250°C)
• NI1000 TK5000 (-30...160°C)
• KT100/110/130/210/230 KTY10/11/13/16/19 (-50...150°C)
• KTY81/82-110,120,150 (-50...150°C)
• KTY81-121 (-50...150°C)
• KTY81-122 (-50...150°C)
• KTY81-151 (-50...150°C)
• KTY81-152 (-50...150°C)
• KTY81/82-210,220,250 (-50...150°C)
• KTY81-221 (-50...150°C)
• KTY81-222 (-50...150°C)
• KTY81-251 (-50...150°C)
• KTY81-252 (-50...150°C)
• KTY83-110,120,150 (-50...175°C)
• KTY83-121 (-50...175°C)
• KTY83-122 (-50...175°C)
• KTY83-151 (-50...175°C)
• KTY83-152 (-50...175°C)
• KTY84-130,150 (-40...300°C)
• KTY84-151 (-40...300°C)
• KTY21/23-6 (-50...150°C)
• KTY1x-5 (-50...150°C)
• KTY1x-7 (-50...150°C)
• KTY21/23-5 (-50...150°C)
• KTY21/23-7 (-50...150°C)
• B-Parameter
• DIN IEC 60751
• Steinhart Hart

The Pt types are implemented according to DIN EN 60751/IEC751 with

• A = 0.0039083 °C^-1
• B = -5.775 * 10^-7 °C^-2
• C = -4.183 * 10^-12 °C^-3

and therefore α = 0.003851 °C^-1. If other coefficients are required, they have to be inserted directly into the CoE via the setting "DIN IEC 60751". For calculation with α only, the CoE Scaler 0x80n0:2E "linear" have to be used.