McQuay MicroTech II User Manual

OM 780-2 Page 55
Figure 21. External Reset (English)
40
44
49
54
System Setpoint (°F)
Max System Spt= 54°F
Min System Spt= 44°F
0246 108
04812 2016
External Signal
0–10 Vdc:
0–20 mA:
a0150
Figure 22. External Reset (SI)
System Setpoint (°C)
Max System Spt= 12°C
Min System Spt= 7°C
0246 108
04812 2016
External Signal
0–10 Vdc:
0–20 mA:
5
7
12
11
10
9
8
6
a0151
For example, if the settings of Figure 21 and Figure 22 are used, the following occurs when External reset is selected:
External Analog Signal Corresponding System Setpoint
4 mA 44.0°F (7.0°C)
12 mA 49.0°F (9.5°C)
20 mA 54.0°F (12.0°C)
You can monitor the current value of the External Chilled Water Reset Signal on the Misc screen of the user interface.
Note that in all cases the displayed value is a conditioned value of 0–10 Vdc.
To set up External reset
1. Set the Chilled Water Temperature Reset Type variable to “External.”
2. Set the following variables as required:
• Minimum System Setpoint
• Maximum System Setpoint

McQuay MicroTech II Specifications

General

Brand	McQuay
Model	MicroTech II
Category	Controller
Language	English