i have a customer who built a new building about
200 ft from the existing shop, we placed a buried
25 pair cable, on it and bonded it etc, he has a problem with his phone out there, and claims it wont work on this cable, is there a maximum length of cable on a comdial key tel, we are about 400 ft from the cabinet. thanks for any help,

Digital sets run 1500 to 2500 ft depending on the gauge of the wire.

you can double up on the pairs. I had a DXP working sets about a half mile away some years ago. I tested by taking 3 boxes of wire and chickleting them together with a jack on the end, they worked fine so we strung the cable.

200 ft is no problem. It has to be something else. Bad protection? bad punch etc. It is not the distance

Jim

First, we need to hear from you as the type of problem he claims to be having.

Is it one or more of these? NDT, CH, CBH, CBDT, GWN, BDR, BRCM, NSY, HOOL, GCO ?

Have you tried swapping his phone with a known working one?

Have you taken his phone back to the main building and plugged it into a known working jack?

Have you tried using a different pair in the cable?

Have you tested the pair with a vom for metallic faults?

Have you tried temporarily by-passing the protection at one end? at both ends?