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Analog outputs, Wiring the dual dac, Analog outputs 39 – Watlow CPC400 User Manual

Page 53: Figure 2.27—dual dac with current output 39

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CPC400 Series User’s Guide

Chapter 2: Installation

Doc. 0600-2900-2000

Watlow Anafaze

39

Analog Outputs

Analog outputs can be provided by using a Dual DAC or Se-
rial DAC module to convert the open collector outputs from
the controller. Use multicolored stranded shielded cable for
analog outputs. Analog outputs generally use a twisted
pair wiring. The following sections describe how to connect
the Dual DAC and Serial DAC modules to power the con-
troller outputs and the load.

Wiring the Dual DAC

A Dual DAC module includes two identical circuits. Each
can convert a distributed zero cross (DZC) signal from the
controller to a voltage or current signal. Watlow Anafaze
strongly recommends using a power supply separate from
the controller supply to power the Dual DAC. Using a sep-
arate power supply isolates the controller’s digital logic cir-
cuits and analog measurement circuits from the frequently
noisy devices that take the analog signal from the Dual
DAC.

Several Dual DAC modules may be powered by one power
supply. Consult the Specifications chapter for the Dual
DAC’s power requirements. Also note in the specifications
that the Dual DAC does not carry the same industry ap-
provals as the Serial DAC.

Figure 2.27 Dual DAC with Current Output

TB50 or TB18

+5V 1

Control Output

+5V CTRL Supply

1

2

3

4

5

6

DZC CTRL PID Output

+12/24V

Î

(dc) External

Power Supply

+V

Î

(dc) Load Connection

-mAdc Load Connection

-External Power
Supply/ V

Î

(dc) Load

Connection

Dual DAC

mA Load

12 to 24V

О

О

О

О

(dc) Power Supply

+ -

+

-