This Standard applies to
(a) power supplies including transformer units of both the direct
plug—in and cord—connected types that utilize a step—down,
isolating transformer of the extra—low—voltage secondary type and
that may incorporate rectifiers and
CSA C22.2 No.223-M91-CAN/CSA-1991 history
1991CSA C22.2 No.223-M91-CAN/CSA-1991 Power Supplies with Extra-Low-Voltage Class 2 Outputs General Instruction No 1; Second Edition