Analogue Output Module; Ao-3: Analogue Output Module; Overview - semaphore KINGFISHER PLUS+ Hardware Reference Manual

10. ANALOGUE OUTPUT MODULE

The AO-3 analogue output module provides four 12-bit current loop outputs allowing a
Kingfisher Plus+ RTU to drive analogue loads.

AO-3: Analogue Output Module

10.1.1 Overview

• 12 bit resolution
• 3 kV field to logic isolation
• Open loop detection
• 0 – 20 or 4 – 20 mA outputs
• 3 kV channel group to channel group isolation
The AO-3 provides four current output channels that use 12-bit digital to analogue
converters (DAC). The AO-3 also provides open loop detection.
The sign bit is not used in the digital to analogue conversion process. The placement of the
12 bits within the data word is as follows:
MSB
0 D11 D10
This module provides two output ranges. The default range is 4 to 20 mA with user data
scaled so that a count of 0 corresponds to 4 mA and a count of 32760 corresponds to
20 mA. A range link (on the rear of the module) selects either 4-20 mA or 0-20 mA for all four
channels. The default condition is 4-20 mA with the link on. The module provides 12 bits of
resolution in either range.
Scaling of the output is shown below.
Hardware Manual Version 7.16
D9 D8 D7 D6 D5
http://www.servelec-semaphore.com/
Kingfisher Plus+ Hardware Manual
D4 D3 D2 D1 D0
LSB
0 0 0
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