Rockwell Automation 2364F Regenerative DC Bus Supply Unit (RGU) - Manual (Page 118)

Publication 2364F-5.01– October 2003
11-6 Configuring Analog Input and Output Parameters
1. Select P49 (DAC1 Indirect) and enter 143.
P49 will allocate P143 as the source of output for Analog Out 1.
2. Select P50 (DAC1 Offset) and enter 0, then select P51 (DAC1
Gain) and enter 0.33.
The range of our source parameter (P143) needs to correspond with
the desired range of the DAC1 Output (P47). To do this, we set the
gain and offset.
Possible range of P143: 0-1050 (volts) / 0-6144 (internal units)
Desired range of DAC1 Output: 0-2047 (which corresponds to 0-10V)
It is the internal units of P143 are sent to the DAC1 Output. Here is
how we can calculate the maximum internal units of P143.
The offset and gain needed to adjust P143 (0-6144) to the range of
P47 (0-2047) can be calculated as shown below.
(P143 + Offset) x Gain = P47
(0 + Offset) x Gain = 0 (Min)
(6144 + Offset) x Gain = 2047 (Max)
The minimums are both zero, so for this example, we can set the
offset to 0, and can just determine what multiplier (gain) would be
needed.
6144 x Gain = 2047
Gain = 0.333
Setting P50 (DAC1 Offset) to 0 and setting P51 (DAC1 Gain) to 0.33
will result in a range of 0-2047 being sent to the P47 (DAC1 Output),
which is what we want.
3. Select P52 (DAC1 Cutoff Frequency) and enter 0.5. Since this is
monitoring a DC value, the filter can be set to a low value.
4. Select P47 (DAC1 Output) to view the values being sent to the
D/A converter. The values in P47 (0 to 2047) should correspond
to the magnitude of the output (0 to +10V).
Formula for P143 Internal Units
P16 = 700 in a unit
with a 460V AC input
Max Internal Units
Max User Units 4096
×
P16
---------------------------------------------------
1050 4096
Ч
700
----------------------------- 6144 = = =