.
-
,~ . .
,.~~:,..j
~~~
8ectrical
~
" Authority
I
May 2006
Working to Better Meet Your Needs
.
..
.
ESA'sFieldEvaluationServicesdedicatedCustomerServiceCentreis locatedat:
1 Terence Matthews Dr, Suite 130, Ottawa, Ontario, K2M 2G3. You can reach the Centreto requestor to follow-upon Field
EvaluationServicesby one of the followingfour methods:Phone 1.800.559.5356,or local (613) 271.1489; by Fax at 1.800.559.
5358,or local (613) 271.6441; or electronicallyat field.evaluation@electricalsafetv.on.ca.
You may also visit our NEW website at
www.esapa.biz.
ESA'sFieldEvaluationServicesis licensedto applyCSAlabelsthat are nationallyrecognized.
ESA'sField EvaluationServicesGrouphas receivedAccreditationfrom the StandardsCouncilof Canadamakingour label Nationally
Recognized
British Columbiahas now officiallyrecognizedour label bringingour count to eight AuthoritiesHavingJurisdictionacrossthe country
with othersexpectedin the nearfuture
New:
.
.
.
..
On May25thFieldEvaluationswill welcomeour newestteammember,inspectorGordMatlashewski,to the londonlWindsorarea.Gord
can be reachedby calling519-971-1012.
ESA'sField EvaluationServicesGroupofferssameday processingon all applicationsreceivedbefore2:00p.m.- pleaserememberto
include your account number on all correspondenceand If your company requires a POI for payment, please include the
PurchaseOrder Numberwhen submitting your applications.
Pleasecontinueforwardingyour invoice payments to the AccountsReceivableDepartment,PO Box 24143, PinebushPostalOutlet,
Cambridge,OntarioN1R8E6.
Personalizedapplicationformsare availableto streamlineyourrequests contactour CustomerServiceCentre.
Look for ESA's Field Evaluation booth at this years I.EAI. Convention in the fall of 2006 in Ottawall
-
Update
- Technical
Requirements:
LIMITATIONS OF "SLASH" VOLTAGE RATINGS OF "IEC TYPE E COMBINATION MOTOR
CONTROLLERS" (AND OTHER EQUIPMENT)
Summary
The electrical world has changed significantly and now there are many, many choices and options when
purchasing and designing electrical systems. Just when you think you have seen everything, something
else comes along to surprise you.
All "IEC Type E Combination Motor Controllers" marked 600/347 volts V or 480/277 volts V, are not
suitable as branch circuit protection for motors on Delta or Resistance Grounded Systems rated at 600
volts or 480 volts. There are quite a few new systems that are "Resistance Grounded" so be careful how
you apply IEC Type E Combination Motor Controllers. We recently saved a customer a lot of frustration
and money by catching this problem early in the design stage.
Other equipment such as circuit breakers and supplementary protectors may also be marked with these
"Slash" voltage ratings and the same issues apply.
FECNS#8
Background:
Our experience is that if something is rated 600/347 volts then it is obviously OK for 600 volt delta systems
or 600 volt resistance grounded systems. But this is wrong.
The standards allow equipment such as an "IEC Type E Combination Motor Controller" to be marked
600/347 volts Y (called a Slash Rating). But this is not a 600 volt rating.
The manufacturer that marks it 600/347 is actually trying to help us understand the application issues. A
device that has a slash voltage rating has gone through testing
under special conditions. This special testing consists of the lower voltage of the two marked voltages
imposed across a single pole of the device during the interrupting testing for the device. For example, a
device rated and marked 600/347 V is only tested with 347 volts across a single pole not the full 600 volts.
Buyer Bewarel So if we have an IEC Type E Combination Motor Controller rated at 10,000 amperes at
600/347 Y, it is only tested at interrupting fault current at 347 volts. It has not been tested to interrupt
current at the full phase to phase voltage of 600 volts.
On a 600 volt delta system, one has the indicating lights to show the first phase has gone to ground. So
after the first phase going to ground, you actually have one of the phase conductors connected to ground,
but of course no current flows. If any other single pole then shorts to ground, the single pole experiences
the full "phase to phase" voltage of 600 volts, not the 347 volts it has been tested to. The same logic
applies to a resistance grounded system.
An IEC Type E Combination Motor Controller marked 600/347 is not suitable for a 600 volt Delta system. It
is not suitable for a 600 volt resistance grounded system.
If a Type E Combination Motor Controller tried to interrupt the currents in the range of the marked
interrupting rating of 600/347 on a 600 volt delta system (or a 600 volt resistance grounded system), the
device would explode.
Manufacturers are continuously testing and changing ratings, so data sheets are the best way to go on
checking this. Once this is better known, manufacturers will probably start testing these devices at higher
voltages and at reduced fault currents and this data may be available at a later date.
Yes, it has become very time consuming to properly select Type E motor controllers and branch circuit
protection.
This is a very complicated area and we will be pleased to consult with you early in the design stage to
resolve any issues ASAP.
For a consultation for your equipment approvals, call our Customer Service at 1-800-559-5356.
You can find this Newsletter and other helpful information on our website at www.esapa.biz
Thank you,
GeneralManager
ElectricalSafetyAuthority
FieldEvaluationsServicesGroup
FECNS #8