Searching for the right mix of cable(s) features for the dual mono power supply for the Pearl 2.
Found this Harwin Unveils New Twisted and Shielded Cabling Solutions for Gecko Products | Harwin
Thinking each board should/will have a stand alone shielded power umbilical cable with twisted conductors to minimize inductance.
Understanding that the cost will drive actual parts used "used for space" equals expensive assembly.
Thoughts? Good enough? How would you make it?
Found this Harwin Unveils New Twisted and Shielded Cabling Solutions for Gecko Products | Harwin
Thinking each board should/will have a stand alone shielded power umbilical cable with twisted conductors to minimize inductance.
Understanding that the cost will drive actual parts used "used for space" equals expensive assembly.
Thoughts? Good enough? How would you make it?
Attachments
Umbilical mono PSU to Pearl idea evolution
Umbilical project progression:
Scrapping previous concept. With more than three hundred views with no technical feed back this idea will rest until proper application appears ...
New concept uses USB 3.0 cables shielded, bulkhead feed thru, short cable in chassis and breakout boards to allow wires to one pearl board or PSU.
Requirement worst case 100ma load (for two channels)~ 25-30v dc 3w. sSo within specification of USB 3.1 cables. Possibility with 3 sets of signal pairs (signal wires are twisted shielded pairs) to increase wire area per run if necessary for power.
Will include part numbers/pictures with a sketch if any interest manifest itself.
Other concepts involve building umbilicals from scratch using DB9 connectors, DB9 feed thru, twisted wires, shielded with aluminum or copper tape. Shrink wrapped, routed to DB9 breakout PCB for wire attachment to pearl board and PSU.
Another concept omits feed thru connectors entirely and hardwires shielded twisted cable to pearl boards (old school).
Umbilical project progression:
Scrapping previous concept. With more than three hundred views with no technical feed back this idea will rest until proper application appears ...
New concept uses USB 3.0 cables shielded, bulkhead feed thru, short cable in chassis and breakout boards to allow wires to one pearl board or PSU.
Requirement worst case 100ma load (for two channels)~ 25-30v dc 3w. sSo within specification of USB 3.1 cables. Possibility with 3 sets of signal pairs (signal wires are twisted shielded pairs) to increase wire area per run if necessary for power.
Will include part numbers/pictures with a sketch if any interest manifest itself.
Other concepts involve building umbilicals from scratch using DB9 connectors, DB9 feed thru, twisted wires, shielded with aluminum or copper tape. Shrink wrapped, routed to DB9 breakout PCB for wire attachment to pearl board and PSU.
Another concept omits feed thru connectors entirely and hardwires shielded twisted cable to pearl boards (old school).
I’m beginning the planning and gathering of parts for a pearl 2 build. I’m going to go with this psu board and case:
PCB for bi-polar caps/bridge rectifier (for Pass Pearl 2)
My umbilical will use a similar cable gland as shown in the link. I’ll use a 4 pin xlr on the main chassis. I’m planning to use a some Mogami mic cable that I have on hand plus some techflex to dress it up. The cable is shielded with 4 conductors. I’ll use 3 of 4 for power and snip the extra. I’m thinking I’ll terminate the shield at the power supply chassis. I’ll do a bit more reading before building though. Either way, I’ll have the ability to terminate shield on either end.
PCB for bi-polar caps/bridge rectifier (for Pass Pearl 2)
My umbilical will use a similar cable gland as shown in the link. I’ll use a 4 pin xlr on the main chassis. I’m planning to use a some Mogami mic cable that I have on hand plus some techflex to dress it up. The cable is shielded with 4 conductors. I’ll use 3 of 4 for power and snip the extra. I’m thinking I’ll terminate the shield at the power supply chassis. I’ll do a bit more reading before building though. Either way, I’ll have the ability to terminate shield on either end.
I believe (please someone correct me if I'm wrong) it's bad form and dangerous to use widely accepted connectors for other than their intended uses. Maybe not so much that your application can't handle the connectors/cables. But what happens when someone plugs in the correct device into your incorrectly used connectors? Think what would happen if I plugged a USB drive into the Pearl 2 power supply.
Yes I thought of connector/interconnector problem (s) with commonality which originally dissuaded me but looking at the design of the USB cables as it appears to be almost perfectly designed (less flawed).
Address issue by installing at least some sort of breaker, fuse protection inline to DC output. Of course will need to demonstrate safety (the fun part) by sacrificing a Memory stick for testing. My guess is the memory stick will fail without breaching its packaging.
Another preventative and mitigating measure is labeling cables and chassis outputs with flags "Not for use with unauthorized electronics" (two cables two outputs per chassis supply). Lockout the cable with to prevent removal and wrong usage. Simple keying of connectors making them unique to this application such as a pin to prevent normal USB installation to PSU port.
I was really put off by ac power connector types that could be misused when DC application meets with line level. So those will not be considered for the purpose also the shield does not cover the supply wires at the connector barrel mate very well (no easy termination).
Other thoughts about commonality use danger is that all connectors potentially have the same risk such as XLR, ISBN, JST, DB9, banana plug, barrel audio, barrel power.....and perhaps hundreds of others new and old.
Yes the old school cable with no connectors breaks looks more robust than ever and cheaper.
Address issue by installing at least some sort of breaker, fuse protection inline to DC output. Of course will need to demonstrate safety (the fun part) by sacrificing a Memory stick for testing. My guess is the memory stick will fail without breaching its packaging.
Another preventative and mitigating measure is labeling cables and chassis outputs with flags "Not for use with unauthorized electronics" (two cables two outputs per chassis supply). Lockout the cable with to prevent removal and wrong usage. Simple keying of connectors making them unique to this application such as a pin to prevent normal USB installation to PSU port.
I was really put off by ac power connector types that could be misused when DC application meets with line level. So those will not be considered for the purpose also the shield does not cover the supply wires at the connector barrel mate very well (no easy termination).
Other thoughts about commonality use danger is that all connectors potentially have the same risk such as XLR, ISBN, JST, DB9, banana plug, barrel audio, barrel power.....and perhaps hundreds of others new and old.
Yes the old school cable with no connectors breaks looks more robust than ever and cheaper.
Wow sound like you have a great plan. You might investigate shield termination i have seen lots of options.. ferrite beads, resistors, diodes or straight to the connector. Perhaps a good space to experiment.
