Author Topic: REN - Ringer Equivalency Numbers  (Read 24588 times)

Offline Phonesrfun

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Re: REN - Ringer Equivalency Numbers
« Reply #45 on: January 06, 2013, 01:22:01 PM »
Dag:

Your measurements seem to show a REN of .76 for a WE 500, where I have always thought that the 500 was somewhere at about .9, rounded to 1.0.  Could that difference be due to frequency?  In Norway, you apparently have 25 HZ ringing current.  perhaps I will answer my own question by going back and looking at what Ralph says in the book.  You are more up to date on the reading than I am.
-Bill G

Offline dsk

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Re: REN - Ringer Equivalency Numbers
« Reply #46 on: January 06, 2013, 03:40:38 PM »
You are right, I have used the setup described by Ralph O Meyer, but used 25HZ. This is compensated by using a load of 8000 ohms as 1 REN instead of 7000 at 20Hz.
What I measured is true, but the the power-supply is frequency divider, how clean the Sinusoid current actually are is unknown. The phones of equal type may also wary quite much, so the values may be just an indication.

All help and hints are welcome.

dsk

Offline AE_Collector

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Re: REN - Ringer Equivalency Numbers
« Reply #47 on: January 06, 2013, 08:07:08 PM »
I have merged up several "REN" discussions here now. (NOT) Surprisingly, "dsk" seems to have been involved in most of them if not all of them!

Terry

Offline dsk

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Re: REN - Ringer Equivalency Numbers
« Reply #48 on: January 07, 2013, 04:31:14 AM »
 :D REN is an interesting unit. Seems quite logic, just like CANDLEPOWER. Wen it comes to real practical life, its not simple at all.  D.c. resistance has been used, and many collectors has used resistors to adjust the resistance of the circuit.
At the moment all this seems to be indications. When you run different ringers with equal data, some are ringing more easy than others.  Traditionally the high ohm ringers were used at long lines with weak signals, but the mechanical design may be important.

Any conclusion? Not exactly, I have much more to learn.

dsk

Some thoughts added later:

The force from an electromagnet is described here: http://tinyurl.com/bku87lz
The frequency is no issue in those consideration, but if the ringer is made for approx that frequency we could optimize the sensitivity of the ringer, for later make it work at the lowest possible electric load. The easy movement is important, a shorter gap (less way to move for the clapper)
This will give a softer ring, with less sound volume, but I have noticed the still loud volume.
This has of course to be followed by adjustment of the gongs. Positioning the gongs as near as possible to each extreme rest position of the clapper, but not touching works well.
This is not so easily adjusted at single coil ringers, as older twin coil ringers. Frequency ringers are far out of this, because the resonant frequency is tuned in to all parts of the ringer.

If you want to many ringers, you may have to live with bell tinkling, and skip the using of the bias spring.
« Last Edit: January 07, 2013, 07:24:01 AM by dsk »

Offline George Knighton

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Re: REN - Ringer Equivalency Numbers
« Reply #49 on: January 07, 2013, 08:11:46 AM »
If you want to
  • many ringers, you may have to live with bell tinkling, and skip the using of the bias spring.
There's gotta be something wrong.  That's just waaaaay too simple an answer!
Annoying new poster.

Offline GTE Rick

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Re: REN - Ringer Equivalency Numbers
« Reply #50 on: January 12, 2013, 05:41:29 PM »
Did Bell & GTE calculate REN Differently?  I was looking at the bottom of some GTE/AE phones and saw these stickers on the bottom
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Offline Babybearjs

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Re: REN levels
« Reply #51 on: February 09, 2013, 01:02:21 AM »
problem solved.... bias springs in high position. all phones are ring now. disconnected ringers on 2 of them, too loud!
John

Offline dsk

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Re: REN - Ringer Equivalency Numbers
« Reply #52 on: December 13, 2015, 03:52:37 PM »
This document could be of interest.   http://www.ti.com/lit/an/slua060/slua060.pdf
Here they design a ringer power supply at 125mA and states it to be 10 REN.

dsk

Offline markosjal

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Re: REN - Ringer Equivalency Numbers
« Reply #53 on: December 26, 2017, 12:57:09 AM »
I just posted this
http://www.classicrotaryphones.com/forum/index.php?topic=19475.0

As it seems somewhat relevant to this thread I thought maybe someone from this thread could enlighten me

My question is not about RENs as much as high impedance ringing.

My Grandstream HT503 will not ring an AE Styleline nor a WE Princess 2702BM.

IT WILL ring Mexican Indetel models and Mexican Ericsson Models. Both of these have .33mF Capacitors

Mark
« Last Edit: December 26, 2017, 01:09:51 AM by markosjal »
Phat Phantom's phreaking phone phettish

Offline andy1702

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Re: REN - Ringer Equivalency Numbers
« Reply #54 on: January 21, 2019, 12:35:19 PM »
The UK rule is a home system must only have phones connected that add up to no more than 4 REN. This came in during the early 1980s when people started to buy their phones and also when we changed over to plug & socket, enabling subscribers to easily wire their own extensions so having more than one phone in the house for the first time. The most common phones around at the time were the GPO 7xx series. These had 2x 500 ohm coils in the ringer and an alleged REN of 4 (so you couldn't keep them and also have an extension. But the later 8746 (a 746 pre-configured for plug & socket on delivery) only had a REN of 1. This was because it had the 2x 500 ohm coils replaced with 2x 2000 ohm coils, so about 4000 ohms resistance in total.

What we do now is to add a 3.3k ohm resistor in series with the bell coils of old sets with 2x 500 ohm coils. This gives a total of about 4,300 ohms, which is near enough! The resistor does weaken the bells of the 500 ohm coils slightly, but they still ring.

If teh value of REN is the same all over the world and a 500 set has a REN of 1 (which is what I've always understood to be the case) then I'd assume the 500 is about 4000 ohms. This is way below the 7000 ohms some people have quited here as 1 REN, so maybe that explains why more 500s work than officially should.
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Offline poplar1

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Re: REN - Ringer Equivalency Numbers
« Reply #55 on: January 21, 2019, 03:24:14 PM »
DC resistance of a C4A ringer (in a 500 set or other) is 3650 ohms.
"C'est pas une restauration, c'est une rénovation."--François Martin.

Offline dsk

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Re: REN - Ringer Equivalency Numbers
« Reply #56 on: January 22, 2019, 01:23:04 AM »
As stated by someone earlier in this thread, the REN load is difficult, the impedance is OK, but the impedance change depending on other parts of the system, sometimes even whats inside the ATA.  The idea about adding a resistor is a safe way of rising the impedance with (almost) equal the resistor value. The only drawback is the power reduced by the resistor is turned to heat.  Putting in a capacitor may be better, but will absolutely be more sensitive to changes in other parts of the system. It is not a safe way to calculate the right value of the capacitor, so you have to try.  So far my experience has turned out well by using a capacitor of 1μF or 0.68μF rated 200V or more.

On a single ringer (2*500 ohms) roughly measured the REN load was about 2.04 (Z=3429ohms)with a 1μF capacitor, adding one more in series = 0.5μF the REN load was only 0.78 (Z=8926ohms)  but different 1000 ohms ringers has different characteristics so this makes no safe rule!  Only once I have experienced that the REN load falls with a higher value of the capacitor, and that makes me think; did I get the correct readings?

dsk

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Re: REN - Ringer Equivalency Numbers
« Reply #57 on: January 22, 2019, 03:08:12 PM »
I was looking at the same listing and scratched my head.

In the 1800's a German philosopher put forth that man learns nothing from history.  Ringer Voltage is measured in RENs Ringer Equivalency Numbers.  What is 1 REN.  The voltage used by a WE 500 Ringer.  I know modern phones use much less.

Considering that you can still lease a new 500 and there are huge numbers still out there on lease this is pure cods wallop. Even the latest and greatest in VOIP will run at least two WE 500 and push the voltage through house wiring to do it. Ma Bell could ring at least 4 phones and probably more.

Not true.

It depends on the ATA/VG Device, A lot of enterprise-grade Analog VoIP Equipment will ring 5 (or more) WE500's. I even have one that does this AND Supports pulse dialing too!

It just depends on the equipment it is not 'VOIP' that is literally just a set of protocols! It depends on the SLIC Chip inside of the Analog Gateway equipment.

Offline Jim Stettler

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Re: REN - Ringer Equivalency Numbers
« Reply #58 on: January 22, 2019, 04:05:28 PM »
Not true.

It depends on the ATA/VG Device, A lot of enterprise-grade Analog VoIP Equipment will ring 5 (or more) WE500's. I even have one that does this AND Supports pulse dialing too!

It just depends on the equipment it is not 'VOIP' that is literally just a set of protocols! It depends on the SLIC Chip inside of the Analog Gateway equipment.
Please add links and photos of the equipment you you are referring to.
Otherwise this post will be deleted as useless.
Thanks,
GM
You live, You learn,
You die, you forget it all.

Offline andy1702

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Re: REN - Ringer Equivalency Numbers
« Reply #59 on: January 23, 2019, 03:03:52 PM »
Well it seems from what I've gathered from this thread that at least the US and UK have a very similar definition of what 1 REN is. If  a phone's bell coils have a value of about 4000 ohms it's REN = 1. If it's 1000 ohms then it's REN = 4. So logically 2000 ohms would be REN = 3 and 3000 ohms would be REN = 4.

My understanding is that for UK approved equipment at least, any equipment such as ATAs etc has to be able to power an output with a maximum of 4 REN hanging of it.

I have to say i've never had any problems with the phones I've plugged into a given line. the only time I've noticed weak ringing is if I've added a resistor to a phone I shouldn't have by accident. I did this with a US 554 once before I knew better and the bell clapper would hardly move. There was a fairly well known website that said I had to add the resistor. It just goes to show you shouldn't believe everything you read online! I now only fit resistors to old Uk phones as necessary and would never fit one to a US 5xx series.
Call me on C*net 0246 81 290 from the UK
or (+44) 246 81 290 from the rest of the world.

For telephone videos search Andys Shed on Youtube.