Johnson Controls METASYS ASC Networking And Troubleshooting Manual page 9

6. Connect the DMM across the 24 VAC and the 24 VAC Common
terminal of the ASC. Read the voltage with all typical loads
energized.
A reading of 24-26 VAC is required when the line voltage is nominal.
If you read a value less than 22 VAC, make sure the primary voltage
matches the transformer's voltage rating. For details, refer to the
appropriate ASC technical bulletin and recalculate the VA
requirements for the ASC.
You have now completed ASC installation. If this ASC is to operate in
standalone mode, you are done with this document. If the ASC is to be
connected to the N2 Bus for communication to other devices, go to the
next section, Installing the N2 Bus.
Introduction—ASC and N2 Bus Networking and Troubleshooting Guide 9