Connecting Units In Cascade; Vdc Input Connections; Modbus Interface Connections - Boilers And Water Heaters - Watts Aerco AM Series Operation & Maintenance Manual

AM Series Pool Heater User Manual
SECTION 7: INSTALLATION – ELECTRICAL

7.1.2 Connecting Units in Cascade

The cascade function is reserved for future implementation.

7.1.3 0-10 VDC Input Connections

The AM Series models 500, 750 and 1000 are factory supplied with a Communications Module
(the 399 model can be equipped with one as an option). This allows driving the appliance via a 0-
10 VDC analog input. To do this, you must connect the 0-10 VDC supply between terminals 22
and 23 (see Figure 7-3) in the electrical junction box, and the CH mode (parameter 2003 in the
Installer Menu per Section 9.16 of AM Series Manual GF-146) must be set to 4 (four). When
configured this way, the heater supply temperature is controlled by the analog input 0-10 VDC as
shown in Figure 5-4 where:
•
If the input voltage stays below 1.5V, the heater stays OFF.
•
If the input voltage increases to between 1.5V and 2.0V, the heater start to operate and the
supply temperature stays at the value set for the Minimum CH setpoint (parameter 3018 in
the Factory menu per Appendix B in AM Series Manual GF-146).
•
As the input voltage changes between 2V and 10V, the supply temperature will change
proportionally between the Minimum CH setpoint (parameter 3018 in the Factory menu per
Appendix B) and the Maximum CH setpoint (parameter 3017, in the Factory menu per
Appendix B in AM Series Manual GF-146).
Figure 7-3: 0-10 VDC Analog Input Algorithm
7.1.4 MODBUS Interface Connections – Boilers and Water Heaters
The AM Series models 500, 750 and 1000 are factory supplied with a Communications Module
(the 399 model can be equipped with one as an option). This MODBUS interface can be
connected to drive the unit from a building management device. Refer to the AM Series MODBUS
User Manual (GF-146-MB), which is available from AERCO technical support and the AERCO
website (www.aerco.com).
OMM-0111_B: • GF-146-P • 10/29/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 38 of 47