Replacement Trace SW FET Power Board

[davidbrady]

Folks,

I'm developing a replacement power board for our beloved Trace SW4024 pure sinewave inverters. The NOS (new old stock) supply of replacement boards is quickly dwindling. Although the SW has proven to be an incredibly reliable inverter they will inevitably require new parts. Below is a screen capture of the Eagle CAD software package I'm using to model the schematic and layout the printed circuit card. Once I select the components Eagle will generate a Gerber file which I'll then send to a fab house for manufacturing. I imagine having the manufacturer solder the 52 FETs and assorted support components. I'll then finish the assembly which includes soldering heavy gauge AC and DC power cables, and bus bars. I still need to develop the MOSFET driver cards and test everything.

[Hisham Amaral]

(02-10-2017 19:59)davidbrady Wrote:  Folks,

I'm developing a replacement power board for our beloved Trace SW4024 pure sinewave inverters. The NOS (new old stock) supply of replacement boards is quickly dwindling. Although the SW has proven to be and incredibly reliable inverter they will inevitably require new parts. Below is a screen capture of the Eagle CAD software package I'm using to model the schematic and layout the printed circuit card. Once I select the components Eagle will generate a Gerber file which I'll then send to a fab house for manufacturing. I imagine having the manufacturer solder the 52 FETs and assorted support components. I'll then finish the assembly which includes soldering heavy gauge I/O cables, and DC power cables, and bus bars. I still need to develop the MOSFET driver cards and test everything. I'd like to have assemblies available as early as this summer.

David
I am sure many of the converters excluding Liberty and Country Coach have used the Trace SW4024 inverters. I would think that your parts will be a wellcome news to many coach owner that have the SW inverters.
Another good news from the Guru.

[davidbrady]

Thanks Hish,

It's been fun brushing up on the old EE skills. We're not out of the woods yet. There's still a bunch of work ahead, but I think we're over the hump and shortly there will be fresh parts available for the SW. A challenge is connecting 54 10AWG stranded wires to the board. The original manufacturer soldered them in place. This is easily the cheapest way to go. I'd love to use something like these Han Fast Lock connectors but at $1.50 a piece I'd have $75 into connectors per board, plus they need a 9.5mm pad which would be hard to fit:

[Hisham Amaral]

(02-11-2017 13:36)davidbrady Wrote:  Thanks Hish,

It's been fun brushing up on the old EE skills. We're not out of the woods yet. There's still a bunch of work ahead, but I think we're over the hump and shortly there will be fresh parts available for the SW. A challenge is connecting 54 10AWG stranded wires to the board. The original manufacturer soldered them in place. This is easily the cheapest way to go. I'd love to use something like these Han Fast Lock connectors but at $1.50 a piece I'd have $75 into connectors per board, plus they need a 9.5mm pad which would be hard to fit:

David
Do you think the connection will be effective? On all the air bag connections we required all pins be gold plated.

[davidbrady]

Hi Hish,

Sorry for the delay; I've been immersed in the mosfet driver cards. As cool as the Han Fast Locks are, I'm afraid I don't have the room on the board for them. They need a 10mm diameter base circle which is more than I can free up. Soldering is probably the only approach that will work.

Check out these cool bus bars. These are needed to distribute both the low and high voltage across the board:
  E-FAB_PCB_Bussbars_Stiffeners12162015(1).pdf (Size: 1.14 MB / Downloads: 8)

[davidbrady]

Busily working on the FET driver daughter cards. Here's a screenshot of the DriverCard schematic and PCB layout. There are three of these on the PowerBoard. One for each H-Bridge. One H-Bridge per transformer. I have the DriverCard PCB laid out. Still need to route and select components:

[davidbrady]

Folks,

Here's the ControlBoard schematic. This board uses the Microchip PIC16C57 microcontroller along with 7400 series TTL to drive the mosfet DriverCards, which drive the FETs on the PowerBoard. That's all we need to build an inverter. Once again, I'm back to working the PCB layout and choosing components.

[davidbrady]

Here's the routed Driver Card. Time to shop around for a printed circuit card manufacturing and assembly vendor:

[davidbrady]

Folks,

I'm sending BOM and Gerber files out today for printed circuit card prototypes of the Trace SW4024 Power Boards. It's taken a while, but sometimes life gets in the way! Should have boards back for testing within two weeks.

[davidbrady]

Today I received my first set of prototype printed circuit cards for the Power Boards.