My nifty Samsung TV is rated 100-240, 50/60 Hz.
Per the discussion here:
100-240 indicates a continuous range;
50/60 Hz implies two discrete switchable ranges.
As mentioned in this discussion, 50/60 implies a
range of frequencies between 50 and 60 where the
TV would not operate. Of course, as everyone
recognizes, there is no switch for frequency. And,
the TV would operate at any frequency between 50
and 60.
Even among ourselves (product safety professionals),
we do not apply the rating markings consistently.
There is no justification for expecting the user
to distinguish between a - and a /. The user buys
an appliance locally, and it comes with a cord an
plug for local use. The markings are not read
prior to installation. Neither do the installation
instructions instruct the user to check the ratings
before installation. The manufacturer does this
for the user by shipping a fully configured product
to the retailer.
Table lamps don't have rating markings.
What, then, is the value of the ratings markings?
For that matter, what is the safety function of the
ratings markings?
Finally, for whom are the rating markings intended?
Best regards,
Rich
ps: My wife's Pfaff sewing machine has two ratings:
120 V, 50/60 Hz certified by UL and CSA.
220-240 V, 50/60 Hz certified with CE and others.
The ratings are distinctly separate, but on the
same label. No switch. Its quite clear the unit
operates 120-240 and 50-60.
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