Honeywell CT230-GA Guide D'installation page 6

Installation Guide
Installing the CT230 linked units
Install each CT230 linked unit as follows:
Turn the heating system off at the main electrical panel.
Loosen the bottom screw and remove the CT230 faceplate from
the wallplate. (The screw cannot be completely removed.)
Connect the wallplate to the load (heating cables) and to the
power supply (see wiring diagram on page 6).
NOTE: The CT230 linked units can operate on different voltages
in the same setup (e.g., 5 units @ 120 V and 5 @ 240 V).
Install the wallplate to the electrical box using the provided
screws.
4
Faceplate
Wallplate