POWER PLANT BUILD THREAD

Support for JLM Audio Kits

Moderator: Joe Malone

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

POWER PLANT BUILD THREAD

Postby Joe Malone » Tue Mar 12, 2013 10:31 am

New JLM Audio Power Plant kit. Full 115vac/230vac to +24vdc and +48vdc power supply for running 4 x Neve, Telefunken and RCA BA modules.
+24vdc to +30vdc with 2 x 12vac transformer or +30vdc to +36vdc with 2 x 15vac transformer.

Super compact size for its power. 4.75" (120.65mm) x 2.5" (63.5mm).
Image

Switchable 115vac/230vac. VS sync allows syncing multiple Power plants with one 115vac/230vac voltage selection switch.
Image

Super smoothing capacitor bank and trim pot set able voltage rails for precision.
Image

Easy heatsink or case mount with only one screw to tension regs down. Fits on bottom of 1 unit high case or side of 2 unit high case.
Image

Power Plant PCB 4.75" (120.65mm) x 2.5" (63.5mm)
Image

Power Plant Schematic here
Power Plant Parts List here

Building Power plant is very like our AC/DC kit or Powerstation kit but even easier so see that thread for step by step info here

Simple version of Power Plant kit build.
1. Use the blank PCB to mark out the 5 mounting holes in the metal case position where you are going to mount the Power Plant. (4 corner 3mm holes and 1 centre 4mm transformer mounting screw) (or at least do this before fitting the blue transformer to the PCB).
2. Build PCB from lowest to highest components with values as marked on the PCB. Once everything on top of the PCB is fitted turn it over to fit the 2 x LM317 Regs.
3. The 2 x LM317 regs have there metal tabs away from the PCB. Bend the last 5mm of the 3 reg legs 90degrees down (away from the metal tab).
4. Slide the silicon tube over the reg and hold it down in position while soldering the legs to the bottom of the PCB.
5. Mount Power plant kit into the metal case on the 4 x 6mm standoffs and screws provided.
6. The silicon tubes on the regs should be sitting against the metal surface of the case under the Power plant PCB. Use the large screw provided to clamp the regs down to the case by sliding the screw into the 4mm 5th metal case holes and into the blue plastic thread in the centre of the transformer. Tighten gently so the regs are clamped between the PCB and the metal case.
7. Set voltage selector to your mains voltage.
8. Wire Mains Ground to your metal case (The 4 mounting screws will bring the case ground to reference the 0v or the power plant via 10 ohm bypassed with 0.1uF cap to stop ground loops hums)
9. Wire mains Active via a fuse and power switch to A (Active on Power Plant). Wire Neutral to N (Neutral) on Power Plant). (ALL MAINS WIRING SHOULD BE DONE BY A QUALIFIED TECHNICIAN)
10. Double check wiring and meter mains & metal case grounds is 0 ohm on all panels of the case (if not remove powder coating under screw heads etc under you do have 0ohm to all case panerls)
11. Power up and adjust 24v and 48v rails to there correct voltages before wiring these outputs to anything. Once correct power down and wire +24v and +48v and 0v to audio gear and powr up and recheck voltages are still correct.

Note 1.
VS SYNC is NOT used with one Power Plant kit. It is only used when multiple Power Plant need to use one 115v / 230v Switch. All slave Power plant have there 115v / 230v switch NOT fitted and the 4 wires A, N, X , Y need to be wired connecting these 4 points on all Power plant.
Joe :-)
JLM Audio
Capturing Audio without Injury

koi326
Posts: 2
Joined: Sat Jan 18, 2014 10:27 pm

Re: POWER PLANT BUILD THREAD

Postby koi326 » Mon Jan 20, 2014 9:27 pm

hi, new to the forum hello everyone :)

Having a few problems with a power plant kit build if anyone can help.

On first power up after soldering & check I had the power switch the wrong way and blew my external slow blow fuse. On check over the board also replaced a shorted capacitor.

On second power up I think I may have blown the fuse in the transformer, would just like to check...am now getting resistance ratings of 95-100 ohms on the primary and <2.0 ohms on the secondary? Resistor R6 was fried also.

Presuming that this was caused by a short somewhere b/w T2 terminals and Vout, so have checked all components twice (in circuit readings), and checked for continuity twice with ref to schematic, both tests look ok.

When the board is mounted in the chassis, the 0v and the GND are the same node...i.e. there should be continuity from earth (mains) ground right through to chassis mounting bolts and the Ov terminal? This is the case both times when powered on.

Also just to mention, the instrument case dips under the pcb, so the regs are not screwed tight to the case, am using only the corner bolts for this. Is the screw between the regs into the transformer body required for GND connection?

Is there anything else I am missing re. above?

Also just wondering by way of safe testing at lower voltages, if I run a 16v AC signal from another grounded transformer (to active + neutral on Power Plant), would I be able to get similar ratio voltages out presuming all connections are made e.g. 1v to 3.5v DC approx? Or would there be any problems with this method in terms of GND connections (Power Plant GND to 16v AC T2 GND).

*Update* I received this reply from Joe

I am away until the 28th Jan. powering up on the wrong has a good chance of blowing both regulator ICs as we'll as some caps. The ohms for the transformer sound ok. Switch to 240v and check all 4 winding. Outputs should be about 1ohm each and primary I can not remember if they are roughly 50 to 100 ohm each but they will measure about 10 ohm different from each other from memory. If you have the correct fuse the transformer should fine. There should be 10ohm between chassis and 0v.


So, next I will take the regulators out of circuit and test them on breadboard to check they are still working ok, and then resolder the regs, transformer and new R6.

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Tue Jan 21, 2014 10:24 am

koi326 wrote:hi, new to the forum hello everyone :)

Having a few problems with a power plant kit build if anyone can help.

On first power up after soldering & check I had the power switch the wrong way and blew my external slow blow fuse. On check over the board also replaced a shorted capacitor.

On second power up I think I may have blown the fuse in the transformer, would just like to check...am now getting resistance ratings of 95-100 ohms on the primary and <2.0 ohms on the secondary? Resistor R6 was fried also.

Presuming that this was caused by a short somewhere b/w T2 terminals and Vout, so have checked all components twice (in circuit readings), and checked for continuity twice with ref to schematic, both tests look ok.

When the board is mounted in the chassis, the 0v and the GND are the same node...i.e. there should be continuity from earth (mains) ground right through to chassis mounting bolts and the Ov terminal? This is the case both times when powered on.

Also just to mention, the instrument case dips under the pcb, so the regs are not screwed tight to the case, am using only the corner bolts for this. Is the screw between the regs into the transformer body required for GND connection?

Is there anything else I am missing re. above?

Also just wondering by way of safe testing at lower voltages, if I run a 16v AC signal from another grounded transformer (to active + neutral on Power Plant), would I be able to get similar ratio voltages out presuming all connections are made e.g. 1v to 3.5v DC approx? Or would there be any problems with this method in terms of GND connections (Power Plant GND to 16v AC T2 GND).

*Update* I received this reply from Joe

I am away until the 28th Jan. powering up on the wrong has a good chance of blowing both regulator ICs as we'll as some caps. The ohms for the transformer sound ok. Switch to 240v and check all 4 winding. Outputs should be about 1ohm each and primary I can not remember if they are roughly 50 to 100 ohm each but they will measure about 10 ohm different from each other from memory. If you have the correct fuse the transformer should fine. There should be 10ohm between chassis and 0v.


So, next I will take the regulators out of circuit and test them on breadboard to check they are still working ok, and then resolder the regs, transformer and new R6.

If R6 burns something is wired wrong or metal tag of reg is shorted to chassis or transformer has internal short and there is voltage between 0v and chassis which there should not be. You should be able to test the blown regs in circuit as they will just output the full voltage at there in pin. Worth check all diodes for short circuit. Replace any that test short.
Joe :-)

JLM Audio

Capturing Audio without Injury

koi326
Posts: 2
Joined: Sat Jan 18, 2014 10:27 pm

Re: POWER PLANT BUILD THREAD

Postby koi326 » Tue Apr 01, 2014 7:06 am

The diodes are all checking ok no shorts. Regs replaced. But there is continuity between the 0v pin and the bottom right drill hole beside (C15). I swapped out the 10R resistor, but can't get at it now for any more re-soldering in this area.

If I'm reading your post below (and the schematic) correctly.....there should be the 10R resistor with 0.1u cap in parellel between Ov/PCB GND and the chassis, yes? So I could run this resistor and cap directly from the 0V (or any PCB GND point) to the chassis/mains GND? Also was wondering why is there continuity only at this one case mount pin and not the others. Thanks! :D

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Thu Apr 03, 2014 12:26 pm

koi326 wrote:The diodes are all checking ok no shorts. Regs replaced. But there is continuity between the 0v pin and the bottom right drill hole beside (C15). I swapped out the 10R resistor, but can't get at it now for any more re-soldering in this area.

There should be 10R between the mounting hole marked CASE and 0v. Due to the 10R resistor

If I'm reading your post below (and the schematic) correctly.....there should be the 10R resistor with 0.1u cap in parellel between Ov/PCB GND and the chassis, yes? So I could run this resistor and cap directly from the 0V (or any PCB GND point) to the chassis/mains GND?

Yes

Also was wondering why is there continuity only at this one case mount pin and not the others. Thanks! :D

That is the only mounting bolt the 10R and 0.1uF are connected too to pickup chassis connection.
Joe :-)

JLM Audio

Capturing Audio without Injury

tdodds
Posts: 2
Joined: Tue Sep 05, 2017 5:36 am

Re: POWER PLANT BUILD THREAD

Postby tdodds » Wed Sep 06, 2017 8:22 am

Hi, I just bought this kit and am waiting for it to arrive. I looked at the schematic and noticed the unit uses a LM317 for the 48v regulator. As the LM317 is rated for max voltage of 37 volts, will this be reliable (or even work)??
Thanks tdodds

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Wed Sep 06, 2017 10:22 am

tdodds wrote:Hi, I just bought this kit and am waiting for it to arrive. I looked at the schematic and noticed the unit uses a LM317 for the 48v regulator. As the LM317 is rated for max voltage of 37 volts, will this be reliable (or even work)??
Thanks tdodds


The LM317 can run at any voltage but must have less then 40v between in and out pins to regulate.

LM317 protection clamp cuts in at 40v difference between LM317 in and out pins to protect itself. So the power plant has 40ohms limiting the current on powerup so the clamp current doesn't exceed the 1.5A rating so works perfectly and once power supply is stable there is only about 15v across the reg so power supply regs perfectly and is way under its limit of 40v between in and out.

We have made 1000s of power supplies over the last 30 years all using this circuit for 48v with no problems.

I have also seen similar LM317 circuit used in tube gear for 300v regulators.
Joe :-)

JLM Audio

Capturing Audio without Injury

tdodds
Posts: 2
Joined: Tue Sep 05, 2017 5:36 am

Re: POWER PLANT BUILD THREAD

Postby tdodds » Fri Sep 15, 2017 9:23 am

Joe, thanks for the explanation on the LM317.
I received my kit, built it and it works great. Nice product.
TDodds

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Fri Sep 15, 2017 1:38 pm

tdodds wrote:Joe, thanks for the explanation on the LM317.
I received my kit, built it and it works great. Nice product.
TDodds


Excellent. Great to hear :-)

Please if you have any comments and/or photos of your JLM Audio gear in your rack please put them up on our facebook page at the link below or send them to us by email as we work completely by word of mouth with no paid advertising. Feel free to add your website link and other details if you like 

https://www.facebook.com/jlmaudio1
Joe :-)

JLM Audio

Capturing Audio without Injury

papiblu
Posts: 7
Joined: Wed Oct 25, 2017 10:47 am

Re: POWER PLANT BUILD THREAD

Postby papiblu » Wed Dec 27, 2017 3:06 am

Hi Joe
I fried some resistors of my powerplant these christmas.
The 120 ohms ones.
I want to buy some new ones, but what is the wattage of those 120R resistors??

Thanks a lot

joepus
Posts: 2
Joined: Thu Jan 11, 2018 8:06 am

Re: POWER PLANT BUILD THREAD

Postby joepus » Sat Jan 13, 2018 5:30 am

I need some help. I assembled my power plant, plugged it in and turned it on. everything seemed good. The 24 volt side was hot, maybe 30 volts or so. I dialed it down to 24. The 48 volt side was hot also. It measured 57 volts when I first turned it on. I dialed it down until it read 48 volts. I plugged it in to my 1272 style mic pre, the voltage dropped to 2-3 volts. I have another power supply that I used originally with these mic pres, I plugged it in and it seemed to work, voltage did not drop at all. So I figure I must have a flaw in my power plant but I don't know where to start to look for the error. It looks clean to me, no obvious shorts. Any ideas?

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Tue Jan 16, 2018 5:08 pm

joepus wrote:I need some help. I assembled my power plant, plugged it in and turned it on. everything seemed good. The 24 volt side was hot, maybe 30 volts or so. I dialed it down to 24. The 48 volt side was hot also. It measured 57 volts when I first turned it on. I dialed it down until it read 48 volts. I plugged it in to my 1272 style mic pre, the voltage dropped to 2-3 volts. I have another power supply that I used originally with these mic pres, I plugged it in and it seemed to work, voltage did not drop at all. So I figure I must have a flaw in my power plant but I don't know where to start to look for the error. It looks clean to me, no obvious shorts. Any ideas?


Sorry didn't get the email notification for this post.

OK strange the volts booted so high as the trimpots come set half way so both 24v and 48v rails should have booted around 24 to 28v.

Did the 10R burn at all?

What is the power plant bolted to for the regs to heatsink to?

Are the regs fitted with metal tab away from the PCB and in silicon tubes so they do not short to case or heatsink?

Please email me some photos of the top and bottom of the power plant and any wiring so I can check it over for you. Remove case or heatsink and silicon tubes so I can see.
Joe :-)

JLM Audio

Capturing Audio without Injury

joepus
Posts: 2
Joined: Thu Jan 11, 2018 8:06 am

Re: POWER PLANT BUILD THREAD

Postby joepus » Wed Jan 17, 2018 2:11 pm

I put my Power plant in a plastic box
I read over and over instructions on how to bolt the power plant to metal box, but I ignored it.
I'll purchase a metal case and check the things you asked about
Thanks

User avatar
Joe Malone
Site Admin
Posts: 1572
Joined: Wed Jan 24, 2007 11:35 pm
Location: Brisbane, Australia
Contact:

Re: POWER PLANT BUILD THREAD

Postby Joe Malone » Thu Jan 18, 2018 2:18 pm

joepus wrote:I put my Power plant in a plastic box
I read over and over instructions on how to bolt the power plant to metal box, but I ignored it.
I'll purchase a metal case and check the things you asked about
Thanks


OK cool let me know how you get on with metal case.
Joe :-)

JLM Audio

Capturing Audio without Injury

ccfreimuth
Posts: 2
Joined: Wed Apr 17, 2019 11:35 pm

Re: POWER PLANT BUILD THREAD

Postby ccfreimuth » Thu Apr 18, 2019 3:23 am

Hello everybody, first post here.
I've built the power plant and powered it up without issue, however, I'm getting around 17v and 35v on the 24v and 48v rails, respectively. Adjusting the trim pots doesn't afford the amount of adjusting required, so what did I do wrong here? Mains voltage coming in is accurate. Also, I don't yet have it mounted in the die-cast aluminum enclosure I'm using for it, so would this present an issue when simply testing for these output voltages?
Thanks in advance for your assistance in figuring this out.
Best,
Connor

Return to “JLM Audio Kits”

Who is online

Users browsing this forum: No registered users and 5 guests