Users Guide Owner manual

Extended Modbus OPC Server

Operation and Reference

Read input registers (any data type) from (31001 - 31999) (32001 - 32999) (33001 -

33999) (34001 - 34999) (35001 - 35999)

Maximum Values - 125 registers

4.2.3 Scaling

Use this menu to define the conversion of raw data into engineering units and define that

as a New Style. You may also delete any styles no longer needed.

To add a new style:

1. Select an existing style to base the new one on if available.

2. In the new style menu enter a unique name and check the initialize from box if it is to

be based on the previously selected style or leave it unchecked to use the default style

scaling data.

3. Enter the following data as appropriate.

Units

Raw Minimum value

Raw Maximum value

Scaled Units Minimum value

Conversion selection

Linear

Square Root

4.2.4 Scaling Analog Values for Commander Series Instruments

The first Commander instruments to support MODBUS handled scaling of analog

values in a different way than later instruments. The ABB C200, C300, C1900 and

PR100 instruments use a 12-bit register with a raw range of 0 to 4095. The host must

scale the value to obtain the desired engineering unit value.

Newer models, such as the ABB C100, C150, C250, C500 and PR250 instruments,

place an engineering unit value into one or two 16-bit registers. If two registers are

used, the data type is considered a long integer. Values are represented as positive or

negative integers without a decimal point. If a decimal point is used in the

instrument, additional scaling must be performed at the host.

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