Gain calibration – Rockwell Automation 1771-IFF/A,D17716.5.116 FAST ANALOG INPUT MODULE User Manual
Page 14
1–4
Calibrating Your Module
Publication 1771Ć6.5.116 - July1996
The BTR echoes back the status of each of the channels to verify
calibration. If selected channels were calibrated satisfactorily, the
BTR will reflect this by having their bits set to 1. (In Differential
mode, the upper byte of word 21 in the BTR is not set (bits 8–15
decimal or 10–17 octal are 0).)
Read Block Transfer Word 21
Decimal Bits
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Octal Bits
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Channel
16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
Word 21
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
4. Proceed to Gain Calibration below.
Gain Calibration
Calibrating gain requires that you apply 5.000V, 10.000V or 20mA
(as determined by your range and mode) (Table 1.A) across each
input channel.
1. Apply power to the module.
2. Apply the gain voltage as shown in Table 1.A to all 16 channels
(single-ended) or 8 channels (differential).
3. After the connections stabilize, request the gain calibration by
sending a 39 word block transfer write (BTW) to the module.
Refer to chapter 4.
When the BTW is sent, all selected channels are calibrated (set to
1) shown in Table 1.A. If a channel is not selected for
calibration, its bit is 0. (In Differential mode, the upper byte of
word 39 is not set (bits 8–15 decimal or 10–17 octal are 0).) All
bits in word 38 will be set to 0.
Write Block Transfer Word 39 for Gain Calibration
Decimal Bits
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Octal Bits
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Word 39
16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Chapter 4