This is good stuff, and Mr Nute reminded me of related stuff that UL has
recently changed. Where construction of magnetics incorporates an UL-recognized
Electrical Insulation System, the component can now reference the UL file
number and EIS designation on the label without necessarily having
Dear experts,
We are evaluating DC/DC converter with SELV-in/SELV-out specification according
to IEC 60950-1. We have measured internal working voltages on the transformer
between input and output side and they were above SELV circuit (88Vpk).
Could you please comment following scenarious:
Scott,
Thanks for this, please see my PM.
All the best, Doug
On Tue, Jan 13, 2015 at 9:45 AM, Scott Aldous
0220f70c299a-dmarc-requ...@ieee.org wrote:
Hi Doug,
Rather than start with the number to plug into the formula in the
standard, it would be more helpful to start with the MSA
Hi folks,
Anyone familiar with in IEC 60617-DB:2001 and IEEE 315/315A? Perhaps the older
IEEE standards are just a subset of the newer IEC standard?
-Dave
-Original Message-
From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com]
Sent: Saturday, January 10, 2015 12:05 AM
To:
Hi Brian:
when we attempted this test the motor got hot very quickly and then failed open
circuit
Failure is acceptable provided it is repeatable. In the past, UL would require
three repetitions of the tests to prove that the failure is repeatable; I don’t
know if this is
You can also do a quick validation of the UL status yourself once you get the
UL file number at
http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/index.html and the
motor part number. But it still requires some honesty with the OEM because
the UL certifications will often state
Hi Doug,
Rather than start with the number to plug into the formula in the standard,
it would be more helpful to start with the MSA and derive what number
should be plugged into the formula. I am curious to see what others think,
but I agree with you in that I believe that a +/-1% stated accuracy
With regard to EN61000-6-11 (flicker) and EN61000-6-12 (harmonics) for
equipment with current ratings from 16A to 75A per phase, what is the accepted
definition of a public low-voltage system (standards apply) versus a private
low-voltage system (standards do not apply). Under what
We want to use a small air pump, about the size of an aquarium pump, in one of
our products (laboratory equipment). It has a small 24Vdc brushed motor without
any visible safety certification markings.
In these cases, we usually perform the locked rotor test according to IEC/UL/EN
61010-1
In message
64D32EE8B9CBDD44963ACB076A5F6ABB026CA9B0@Mailbox-Tech.lecotech.local,
dated Tue, 13 Jan 2015, Kunde, Brian brian_ku...@lecotc.com writes:
If the winding overheated and melted open, would this be considered a
fire hazard?
Not just for that reason. Does it emit flame or flammable
Clauses 6, 9, and 10 provide definition of a hazard and a hazardous condition.
Some motors are designed with a section of the winding to act as a fusible
link, so not unreasonable for a section of the winding to melt. In any case, it
is advisable to repeat abnormal operating conditions tests in
Ignore my earlier question...I meant the following:
With regard to EN61000-3-11 (flicker) and EN61000-3-12 (harmonics) for
equipment with current ratings from 16A to 75A per phase, what is the accepted
definition of a public low-voltage system (standards apply) versus a private
low-voltage
I've been told that UL does not necessarily do locked rotor test for
recognized motors, they would for listed. If you can get locked rotor test
data from the OEM you can use it otherwise you need to do it yourself.I
recall the standard says for integrated blowers and such you don't
You still need to do normal (thermal) and abnormal (locked rotor, maybe running
overload) on recognized motors unless you can get actual test data/results done
by the OEM (or UL). That's what I've been running into with my NRTLs. And
only one of my OEMs was able to provide me test data (which
The pump manufacturer just sent me a picture of the motor name plate which must
somehow be hidden from view when installed in the pump assembly. Anyway, the
motor is made in Germany and has the CE marking and the UL Recognized component
mark. Is this adequate to determine the pump/motor is
Clause 16 has that wonderful 'forseeable misuse'. Whatever the rating and
certification of the motor, all of these abnormal operating conditions should
be performed as part of the assessment for the end-use equipment.
As for Listed vs Recognized - not gonna know what was tested until you look
No.
As for an EIS, the UL file will specify this in the respective section's
general description unless the mfr has de-rated the unit, then the max
operating temp will be in the C of A.
Brian
-Original Message-
From: Kunde, Brian [mailto:brian_ku...@lecotc.com]
Sent: Tuesday, January
In message
7B9D892F88F070469771832D78B3086E28437FC1@013-BR1MPN1-013.MGDPBI.global.p
vt, dated Tue, 13 Jan 2015, Jim Hulbert jim.hulb...@pb.com writes:
With regard to EN61000-3-11 (flicker) and EN61000-3-12 (harmonics) for
equipment with current ratings from 16A to 75A per phase, what is the
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