Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

So the SA is not in overload, which could give a wrong amplitude otherwise. Thanks, Michael Sundstrom Garmin Compliance Engineer 2-2606 (913) 440-1540 KB5UKT "Never give up on a dream just because of the time it will take to accomplish it. The time will pass anyway." Earl Nightingale From:

[PSES] Preselector requirement in ANSIC63.4 -low PRF

Hell all, ANSI C63 *requires* the use of a preselector on an SA when making QP measurements of a signal with a low repetition rate (lower than 20Hz or less). Does anyone know why? Best Regards Charles Grasso Compliance Engineer Echostar Communications (w) 303-706-5467 (c) 303-204-2974 (t)

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

I would think that if the measurements were taken in a chamber and the product emissions were characterized and amplitudes known and the analyzer was a good quality one, justification could be made to eliminate the preselector. I suspect the requirement was established during the days we all

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

Hey Ken – thanks! The note in ANSIC63 says that the preselector is required to increase the dynamic range of the instrument. Is it simply a noise floor issue – but then why the <20Hz specificity? Best Regards Charles Grasso Compliance Engineer Echostar Communications (w) 303-706-5467 (c)

Re: [PSES] 208 split-phase?

Most residential high-rise buildings distribute 120/208V throughout the building. Electric ranges and dryers will run from 120/208V or 120/240V ___ Ralph McDiarmid | Schneider Electric | Solar Business |

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

Isn't that the risk for any measurement using a SA, particularly when measuring from an AMN? (peak, QP or AVG) ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

I can see how adding gain ahead of the SA lowers the noise floor, but I don't see how a preselector can do same. A preselector seems most useful in tuning only the frequency band of interest, rejecting (attenuating) the rest.

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

I believe if you do a Linearity Check you can tell if your readings are correct or influenced by a strong adjacent signal. Take a reading, add 10db internal attenuation, and see if you get the same reading. Or add an external attenuator to the input and see if your value decreases by the

Re: [PSES] 208 split-phase?

Many utilities will specify 120 V utilization voltage with a tolerance that results in a range of 104 V – 127 V. Based on Mr. Tarver’s original submittal, I doubt that this 104 V is being confused for what he is asking about. However, it will at least offer it as a possibility. Ted Eckert

Re: [PSES] 208 split-phase?

NEC art 210.4 and 210.5 seem to allow it and the CEC here in Canada certainly allows it. For large residential highrises, it's probably simpler and cost effective to distribute 120/208 throughout the building (1/3 of the suites on one 208 leg, and so on) Phase balancing would be part of the

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

Exactly the procedure I posted in our EMC lab years ago. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: "Kunde, Brian"

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

On 10/22/2015 2:53 PM, Grasso, Charles wrote: ANSI C63 **requires** the use of a preselector on an SA when making QP measurements of a signal with a low repetition rate (lower than 20Hz or less). Does anyone know why? It's likely that a low-PRF, short pulse able to even approach the QP limit

Re: [PSES] 208 split-phase?

I believe NFPA 70 specifies 120/240V for all residential household voltages. -Dave From: McDiarmid, Ralph [mailto:ralph.mcdiar...@schneider-electric.com] Sent: Thursday, October 22, 2015 5:19 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] 208 split-phase? Most residential high-rise

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

A preselector adds dynamic range in the presence of a broadband signal. Ken Javor Phone: (256) 650-5261 From: "McDiarmid, Ralph" Reply-To: "ralph.mcdiar...@schneider-electric.com" Date: Thu, 22 Oct 2015 14:30:45

Re: [PSES] 208 split-phase?

Peter, It doesn’t sound right. Somebody may be describing a 120/240 V, 3-Wire system, and mixing it up with a 120/208 V, Y-connected power. Hope all is well. DON GIES ALCATEL-LUCENT SENIOR PRODUCT COMPLIANCE ENGINEER GLOBAL PRODUCT COMPLIANCE LABORATORY 600-700 Mountain Avenue Room

Re: [PSES] 208 split-phase?

Essentially all residential electrical services in the US are 120/240 volt split phase services. Electricians call this single phase service. As an electrical engineer, I like to think of it as two phase service, with phases at 180 degrees. You will not find residential service provided 208