sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 551 b leads to use

Guys is there a general rule for the spare line cord leads to use when adding 551 buttons to a 2565 2564 2563 set?

Obviously "whatever spare ones you have" is the best answer but i suspect there is a general rule for this like there is for everything else. If there is a BSP I should look at like manual intercom or something like that please advise.

Thanks Much
Shawn

Generally, you would use the Yellow group leads that are not already dedicated for ringer and buzzer.

Before ten-button 830-type sets were made, 6-button sets came out with the ringer on the Yellow/Slate pair and the buzzer on the Yellow/Green pair. The 830-series phones used a very easy-to-remember system of pair assignments, assuming that you used the Yellow/Orange for the buzzer.

So, my advice would be to use any of the remaining Yellow group leads, of which you have 6 to chose from. Remember that the convention in key systems and other customer-operated equipment is to have GRD on the button or key that gets operated by the subscriber, and BAT on the device that gets operated. Therefore, you can derive the GRD supply from several points in the set, (A1 ground, lamp grounds, ringer ground, etc) and that gives you all 6 spare Yellow leads to use for buttons.

Installers of 1A2 systems were given a great deal of latitude in how they wired things, as long as there was consistency in the work. The "balance" leads (the unused --ringside-- halves of the pairs that are assigned as the 2nd, 3rd, 4th and 5th "A" leads) can also be used for miscellaneous devices.

Perfect, thank you Arthur.

YW