How many devices are supported on the RS-485 port (COM3) of the ECC21 card in a CM4000 & CM4000T?

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Issue
How many downstream devices can be connected to COM3?

Product Line
CM4 ECC21 Card

Environment
COM3 = RS-485 Serial Port

Resolution
This port supports up to 31 devices (without a repeater), since the device that holds the ECC card counts as a device. The limit is up to 63 devices with a repeater.