atcomsystems.ca/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems Samsung OS700-High Loop Current

In the US, are these the standards below for a POTS line interfacing with a business telephone system?

When line is not in use: Line Voltage 48 volts DC

When the telephone is off hook: Line Voltage 6 volts D.C.

Ring Voltage: 90 Volts AC

Loop Current: 23 to 35ma range

We have a customer with an OS7100 with Verizon lines that read between 50-70ma loop current.

They are complaining about one way audio on many incoming calls and some outgoing calls.

We have tested and we find the same thing.

Verizon says that they cannot reduce the loop current.

The customer is as far as you can get from the local central office. They are at the end of the line.

Will high loop current cause these problems?

MikeS in VA

are the Phones Digital or IP

what happens when you use a Butt direct on the line?

High loop current will cause you all kinds of weird problems.

The 50 - 70ma is way too high. If Verizon can't reduce it look for some loop current reducers. I think Sandman in Chicago use to have / make some. We've used them and they seem to take care of the problem and protect the equipment.

"The customer is as far as you can get from the local central office. They are at the end of the line."

Distance means nothing these days. They might be fed from a SLC or Lightguide box right around the corner. The current you mention is so high as to almost indicate faulty equipment. OF COURSE they can reduce the current to acceptable levels. They can, and they must, according to tariffs.

Now that I've had a good laugh, take the advice above and see Sandman and get his loop current regulators. Get it down to 35 mA or less and you'll get a good result.

The phones are all digital sets on an OS7100 4.14k Software.

The problem is on all lines.

We do not have the issue when making a call from a butt set.

Thanks,

MikeS In VA

Loop current regulators as previously suggested, the current is way too high. The phone companies have a low but not a high threshold, I've beat this horse several times.