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# How do I scale 0 - 4095 to 6400 - 32000 using 984 Ladder Logic?

Published date: 27 September 2018

The following network scales data from 0-4095 to 6400 - 32,000 when 4-20ma (6400 = 4 mA, 32,000 = 20 mA) outputs are required
but a 0-20ma analog output is used. .

Register 400001 and 400002 are used together in the top node of the EMTH Block, where 400001 is
always 0000 data and 400002 is the variable data, 0-4095, to be scaled. Register 400003, displayed in data
format float, is a fixed floating point value that the user enters as 6.25153 (note that two registers are
used to create the floating point value, 400003 & 400004 in this example). Register 400005 (and 400006)
is the floating point result of the integer and floating point multiplication (EMTH block).

The FTOI (Floating Point TO Integer) block converts the floating point result of registers 400005
and 400006 to an integer value in a single register 400007.

The AD16 block adds the top node register 400007 to the middle node constant 6400 and places
the result in register 400009. This register will then map to one of the analog outputs.

The following data screens shows the input values of 0 and 4095 and there corresponding results.