I have no less than 40 PLC/VFD/HMI cables wadded up in a busted cardboard box in my service vehicle. 75% of them are nothing special; no electronic box in series, just a DB9F on one end and an RJ45 on the other, or a DB9M and a DB15HD or a DB25 or whatever. And they all have some "special" pinout so that some manufacturer could sell some "special" cable at an exorbitant rate.
I inherited them from the retired old timer who I "replaced" (term used loosely; he was a genius/wizard and could never actually be replaced ... I only filled his billet). Probably took him several thousand dollars and 30 years to amass such a collection. In fact, it did. I feel honored to be bestowed with such an impressive collection, but I find it cumbersome at times; not having been present for the addition of each cable to the collection, and in the absence of any kind of identification tag on 90% of them, I don't know what they all are or if/when I'll ever need them.
On more than one occasion I've found myself in the field hacking serial cables in two and crossing this wire with that, or splicing in an ethernet cable, to make the "proper" cable needed based on pinouts downloaded from the internet, only to later find that I had the actual proper cable in my cache but didn't know it when I saw it.
So I thought it would maybe be a good idea to build a professional-looking breakout box. A Serial Swiss Army Knife, with DB9M/F, DB15M/F, DB15HDM/F, DB25M/F, and RJ45. Customers seeing that might be instilled with a little more confidence than seeing me with a hacked up, frayed cable plugged into their PLC as I download. I could retire most of those old cables, and replace them with 3X5 index cards of cable pinouts (kept neatly inside the breakout box enclosure).
I envision a single serial cable (the one that will connect to the PC) entering the box permanently fastened with a gland, with all of its conductors free, ferruled, labeled, and long enough to reach anywhere in the box. Then the following boards mounted with standoffs along the bottom of the box: DB9M/F, DB15M/F, RJ45, DB25M/F, DB15HDM, and DB15HDF. Then I just carry a single M/F straight-through cable of each variety, and make the proper pinout on-site. (plus all the truly special cables like Siemens MPI, AB U2DHP, micrologix et. al.)
What do you think? Stupid rookie idea? Good idea but I'm missing something? How would you do it differently?
EDIT: P.S. I have no affiliation with the Ebay seller in the links.
I inherited them from the retired old timer who I "replaced" (term used loosely; he was a genius/wizard and could never actually be replaced ... I only filled his billet). Probably took him several thousand dollars and 30 years to amass such a collection. In fact, it did. I feel honored to be bestowed with such an impressive collection, but I find it cumbersome at times; not having been present for the addition of each cable to the collection, and in the absence of any kind of identification tag on 90% of them, I don't know what they all are or if/when I'll ever need them.
On more than one occasion I've found myself in the field hacking serial cables in two and crossing this wire with that, or splicing in an ethernet cable, to make the "proper" cable needed based on pinouts downloaded from the internet, only to later find that I had the actual proper cable in my cache but didn't know it when I saw it.
So I thought it would maybe be a good idea to build a professional-looking breakout box. A Serial Swiss Army Knife, with DB9M/F, DB15M/F, DB15HDM/F, DB25M/F, and RJ45. Customers seeing that might be instilled with a little more confidence than seeing me with a hacked up, frayed cable plugged into their PLC as I download. I could retire most of those old cables, and replace them with 3X5 index cards of cable pinouts (kept neatly inside the breakout box enclosure).
I envision a single serial cable (the one that will connect to the PC) entering the box permanently fastened with a gland, with all of its conductors free, ferruled, labeled, and long enough to reach anywhere in the box. Then the following boards mounted with standoffs along the bottom of the box: DB9M/F, DB15M/F, RJ45, DB25M/F, DB15HDM, and DB15HDF. Then I just carry a single M/F straight-through cable of each variety, and make the proper pinout on-site. (plus all the truly special cables like Siemens MPI, AB U2DHP, micrologix et. al.)
What do you think? Stupid rookie idea? Good idea but I'm missing something? How would you do it differently?
EDIT: P.S. I have no affiliation with the Ebay seller in the links.
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