# Power supply setup

**URL:** <https://discourse.nodered.org/t/power-supply-setup/2200>\
**Category:** General\
**Created:** [10 August 2018 08:19 UTC](https://discourse.nodered.org/t/power-supply-setup/2200 "2018-08-10T08:19:34Z")\
**Posts on this page:** 13\
**Page:** 1

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**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [10 August 2018 08:19 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/1 "2018-08-10T08:19:35Z")

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Hi folks,

This question is not NR related, but I think enough brains are avaliable here... I have lots of devices, all with their own voltage levels (5v / 7,5v / 9v / ...). Currently I have some din-rail adapters to 12v, and then I use automotive dc-dc converters from aliexpress to go to some specific voltage levels.

However I would like to build a better solution that:

- Is nice to look at, e.g. everything din-rail?
- Is all CE approved
- Has all kind of fuses. Don't want any of my devices to corrupt my setup
- Has adjustable voltage levels. So I can use the same converters for alk devices.
- Has some visual interface (e.g. LEDs) to see immediately where something is wrong
- Is affordable, since Im married (with a female prototype version 0.0). So I need to save some money to be able to buy a massive amount f shoes 🙂

Thanks!!  
Bart

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [10 August 2018 08:44 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/2 "2018-08-10T08:44:08Z")

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Have a look at the Mean Well MDR Range.  
[https://www.meanwell.co.uk/mdr-20-12.html](https://www.meanwell.co.uk/mdr-20-12.html)

Download the PDF, there are several models there.

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**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [10 August 2018 09:11 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/3 "2018-08-10T09:11:40Z")

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Hi Garry,

Thanks!

Had seen those also, but not sure if I can use them?

 ![IMG_20180810_110652](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/b/bf0a4ec13109992d04be394f25eac04c802f5591.png)

I have devices with 7,5v power adapter for example. Don't think I can adjust one of these power supplies to 7,5v?

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [10 August 2018 09:13 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/4 "2018-08-10T09:13:30Z")

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Bart,  
a voltage regulator on the output of the 12V model should do it.

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [10 August 2018 09:23 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/5 "2018-08-10T09:23:33Z")

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[https://www.st.com/content/st\_com/en/products/power-management/linear-voltage-regulators/standard-voltage-regulators/l78s.html](https://www.st.com/content/st_com/en/products/power-management/linear-voltage-regulators/standard-voltage-regulators/l78s.html)

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**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [10 August 2018 12:56 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/6 "2018-08-10T12:56:36Z")

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Garry,

Currently I have the following setup, a bit similar to what you describe:  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/0/0ed1a2dce6a81f4a8fed4abb523e6ae45d6c7507.jpg)

The grey Siemens (which were way too expensive!) converters do the 230VAC to 12VDC conversion. To each of those converters I have added multiple DC-DC converters (for each of my devices), which you can see at the back of the closet:

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/3/35cd9c52e1bd2869df6790c3b15d08d84451094f.jpg)

These (automotive) DC-DC converters are rather cheap on [Ali](https://nl.aliexpress.com/item/12-V-turn-5-V-3-A-15-W-Car-LED-Display-Power-DC-DC-Converter/32673050807.html?spm=a2g0z.10010108.1000016.1.760b25bdTQNPVd&isOrigTitle=true). They have a fixed output voltage, but I managed to find a separate type for each output voltage that I needed. But they have a few disadvantages:

- As you can see it becomes quite a mess, since they are not din rail.
- One of these was corrupt this morning, and I took me an hour to figure out what was wrong (since they don't have a LED or any other indication). I could a led myself, but then it is again becoming more messy...

Afterwards I also bought this one from [Ali](https://nl.aliexpress.com/item/OOTDTY-DC-4-0-40-to-1-3-37V-LED-Voltmeter-Buck-Step-down-Power-Converter/32579169351.html?spm=a2g0s.9042311.0.0.27424c4dzzeJmQ), since the output voltage is adjustable and nicely displayed on the 7-segment display:

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/6/665113e9417b19cf3a692f3208a82f9f39da507c.jpg)

But here again not easy to fit them nicely into a closet, and you still need separate AC/DC converters to power them.

Your solution would be much more decent: a separate adjustable din-rail for each device. If I could just adjust the voltage to a '_random_' value...

All tips are welcome, since I'm not an electronics expert.

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**Author:** ![ncherry](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ncherry/32/27_2.png) [@ncherry](https://discourse.nodered.org/u/ncherry)\
**Post date:** [10 August 2018 13:57 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/7 "2018-08-10T13:57:31Z")

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I use a [Meanwell 24V DC power supply](https://www.amazon.com/MEAN-WELL-LRS-350-24-350-4W-Switchable/dp/B071FFW996/ref=sr_1_3?ie=UTF8&qid=1533908546&sr=8-3&keywords=meanwell+24v+power+supply) (Amazon) and a [RUIDENG DPS3005 32V 5A](https://www.banggood.com/RD-DPS3005-32V-5A-Communication-Function-Constant-Voltage-Current-Step-down-Power-Supply-Module-Buck-Voltage-Converter-LCD-Voltmeter-p-1161595.html?utm_design=41&utm_source=emarsys&utm_medium=Shipoutinform171129&utm_campaign=newsletter-emarsys&utm_content=Winna&sc_src=email_2671705&sc_eh=dd42f0e28b6693861&sc_llid=265552&sc_lid=104858042&sc_uid=oVshCb6GTj&cur_warehouse=CN). The DPS gives me the ability to adjust the power output, I have a setup with 1 24V supply and 3 DPS devices. I have some older boards that need triple supplies.

There are rules with this, all the DPS devices can't try to use more than 80% of the 24V power supplies rated current.. I generally don't need more than 50%.

The whole thing is pretty easy to wire up. I don't have a case for it but I'm also not using it as a permanent supply. Just as a test bench power supply.

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<div class="post-metadata">

**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [10 August 2018 17:11 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/8 "2018-08-10T17:11:15Z")

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@ncherry solution looks good, if a little expensive. Less shoes then? 🙂

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**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [10 August 2018 19:25 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/9 "2018-08-10T19:25:26Z")

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Hi Neil (@ncherry),  
The ouput voltage range ( **0V-32.00V** ) is indeed something that could be very useful!  
You say you have 3 DPS devices. Do you mean you have 3 of such screens or a single screen that communicates with 3 USB or bluetooth pcb's ?

@ghayne. I should really keep the price a bit under control, because less shoes is not a valid option in wife version 0.0. Seems to be a known bug 😂

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**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [10 August 2018 19:52 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/10 "2018-08-10T19:52:53Z")

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[https://www.aliexpress.com/item/-/32837531202.html?spm=a2g0s.13010208.99999999.259.4cb03c00cxkHAD](https://www.aliexpress.com/item/-/32837531202.html?spm=a2g0s.13010208.99999999.259.4cb03c00cxkHAD)

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<div class="post-metadata">

**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [10 August 2018 21:55 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/11 "2018-08-10T21:55:25Z")

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Here is another DC-DC converter from [ebay](https://www.ebay.com/itm/DC-DC-Adjustable-Buck-Converter-Stabilizer-Step-Down-Voltage-Reducer-W-DIY-Case/282559541237?hash=item41c9dc6ff5:m:mO7aRziSlK0i22JwsHZVW6w) for only 6,29 USD which looks pretty cool:

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/0/00764ee3d24a25316c28db9c61fb0caf58749c43.jpg)

The input voltage range is 5-23V, and the output voltage range is adjustable between 0-16.5V. I could power a series of those converters with a **SINGLE** power supply (like Neil did) which can produce enough amperes. But the main problem is that I have **no** din-rail **case**. Or another case that could be nicely fitted into some kind of closet. Anybody ever seen a nice looking (and expandable) setup?

EDIT: On the above ebay link the same module can be bought, together with an **acrylic case** for 7,34 USD:  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/3/32d81ec1e61b739829c591ef0bbb7afee0492b73.jpg)

Perhaps I can din-rail mount this case somehow, by using those brackets from Aliexpress for only 1,4 USD for a pair of brackets:  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/2/253d4e9cefe1cec217e0ca595df01a9b2d390c23.jpg)

Total amount would be 8,74 USD for each converter, which should survive the wife-acceptance-validation-algorithm...

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<div class="post-metadata">

**Author:** ![ncherry](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ncherry/32/27_2.png) [@ncherry](https://discourse.nodered.org/u/ncherry)\
**Post date:** [11 August 2018 05:47 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/12 "2018-08-11T05:47:07Z")

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Not a bug, an expensive feature.

I have 3 separate DPS devices on the one power supply. I haven't started using the communications interface yet.

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**Author:** ![BartButenaers](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bartbutenaers/32/10476_2.png) [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Post date:** [11 August 2018 07:11 UTC](https://discourse.nodered.org/t/power-supply-setup/2200/13 "2018-08-11T07:11:48Z")

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Had found last night also some other Meanwell devices. Not very expensive, but no voltages between 5,5 V en 10 V. Strange. Have send them a mail about it, but don't expect a positive answer ...

@ncherry: I like the display part of your solution, since I allows me to do some troubleshooting very quickly. So meanwhile I have been looking for some other modules on Aliexpress (with display and acrylic case). Don't know which to choose... Does anybody can assist me in choosing the best option (e.g. on some devices I don't find info about **_short-circuit and terminal protections_**...)?

- [This](https://nl.aliexpress.com/item/Power-Supply-Module-DC5-23V-to-0-16-5V-3A-Buck-Converter-Adjustable-Voltage-Regulator-Adapter/32789361261.html?spm=a2g0s.13010208.99999999.304.3ca13c00A21hVF) is the same as the one on ebay for 10,5 USD:

- [This](https://nl.aliexpress.com/item/-/32886481960.html?spm=a2g0s.13010208.99999999.272.30453c00kkGwx9) is bit less expensive, but you need to pay shipping. In my case (Belgium) total cost is 9 USD:

- [This](https://nl.aliexpress.com/item/LCD-Liquid-Crystal-Displays-DC-DC-Step-Down-Buck-Converter-Power-Supply-Adjustable-Push-Button-Module/32767698882.html?spm=a2g0s.13010208.99999999.266.30453c00kkGwx9) is already available at 4,58 USD:  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/5/555f81474a3dfab5a37f160558df6e39641386ac.jpg)

- [This](https://nl.aliexpress.com/item/-/32891103974.html?spm=a2g0s.13010208.99999999.259.30453c00kkGwx9) one has an intermediate price of 7,81 USD:

P.S. I'm not one of the main shareholder of Aliexpress 🕶