How many CTs are needed for 3-phase 3-wire, and other phase formats?

For each power monitor, normally you use 1 to 3 CTs.
Single phase 2-wire = 1 CT; single-phase three-wire = 2 CTs; three-phase three-wire = 2 CTs, and three-phase four-wire = 3 CTs.

PR201 Power Monitors

The PR201 Power Monitors was discontinued on 1/01/2006. The PR300 is a replacement product.
UPM01

Model Name: UPM01
UPM02

Model Name: UPM02
UPM03

Model Name: UPM03
UZ002

Model Name: UZ002
UZ003

Model Name: UZ003
UZ005 Power Monitors

The UZ005 Power Monitors was discontinued on 9/01/2006. The PR300 is a replacement product.
UZ008

Model Name: UZ008