Code Corner 2005.4
In the heat of the summer, most of us have experienced either
a brown out or a black out. At home it can be inconvenient, but
rarely life threatening. The same cannot be said for a hospital,
airport, and transportation facility that require a reliable source
of standby power in an emergency.
Emergency generators are the most common source of standby power,
but proper testing of elevators on the generator system is not
a common practice. The Code is very clear on these requirements,
yet we find that the vast majority of owners and maintenance companies
we talk to do not understand the requirements. This misunderstanding
can lead to failures of either the elevator or the generator itself.
Requirement 8.11.2.2.7 of the ASME A17.1 Code regarding existing
elevators on standby power requires an annual test of the elevator
on standby power. If more than one elevator is capable of operating
on standby power simultaneously, then they must be tested on standby
power simultaneously. This test can be performed with no load on
the elevator.
While this test is simple, it is often neglected or postponed
to the point that it is often forgotten. It is our strong recommendation
that all parties responsible ensure that this annual test is completed
in coordination with the maintenance contractor, owner, and the
emergency generator contractor without fail.
If the annual test is forgotten or postponed, consider the five-year
test requirements. This test is identical to the annual test with
one very significant difference. 8.11.2.3.5 Emergency and Standby
Power Operation states operation of elevators equipped with emergency
or standby power shall be inspected and tested for conformance
with the applicable requirements (Item 1.17.2). Passenger elevators
and freight elevators permitted to carry passengers (see 2.16.4)
shall be tested with 125 percent.
If an elevator has been modernized with a solid state drive, the
need for this test is even more important. This is due to the new
electrical characteristics installed that may adversely impact
the emergency generator system. For more information on elevators
and emergency power, visit our technical library.
We at VTX deal with code issues on a regular basis. It is very
likely that your question is not new to us, and we can help quickly.
It is not uncommon for us to bring a request for interpretation
for our clients before A17.1. Just remember that ASME wants the
requirements to be clearly understood, so get it clarified, it
could dramatically affect your project or operation!
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