Difference Input voltage range on datasheet and nameplate

Sometimes you may see a difference in the input voltage range on the datasheets and nameplate seals of the same AC-DC converter or power supply. For example, DRB15241 from TDK-Lambda is an AC-DC converter. When looking at its datasheet, this converter’s input voltage range is from 85-264VAC.

But its nameplate seal shows its input range from 100-240VAC.

Why is there a difference between the datasheet and the nameplate seal of the same product?

The input range on the power supplies (name plates) are the figure used when applications for safety standards are submitted, so that approval of the safety standards is already granted at the time of use within these ranges. Moreover, the datasheets shown are just the input ranges within which the manufacturer assures correct operation of the device. If you operate the supply within the specifications given on the datasheet the part is still specified to work, but it does not conform to the safety standards approvals it would otherwise carry if operated within the specifications on its nameplate.

As an example, DRB15241’s input voltage range allows a single phase rated anywhere from 85-264 VAC, but not under safety approved conditions. For cases where conformance to various safety specifications (UL, CSA, EN) are required, input voltage range must be constrained to within 100-240VAC (50/60Hz). Most importantly, any input voltage which is out of specification entirely (lower than 85V or higher than 264V) may cause the unit damage.