NoDrain (new keyed version)

Negative to +5V converter
  • Keyed connector guarantees orientation and alignment (new!)
  • Offers up to one amp of precise 5Volts
  • Takes its power from where you won’t use it: the negative rail
  • Gives you back the +12V power previously used to make 5V
  • LED indication of 5V conversion
  • High efficiency conversion: Every milliamp delivered on the 5V rail only draws around half as much milliamps on the -12V rail
  • Soft-start prevents current inrush at power-on
  • Tolerates wide voltage variations of the -12V source
  • Miniature module 20x28mm - 0.78x1.10"
  • Adjustable output voltage - delivered calibrated
  • Protected against:
    • Current overload
    • Input overvoltage
    • Overheating
    • Short-circuit
    • Reverse insertion

Old version

The previous version of the NoDrain has its connector on the same side as the components.
It also requires special care during insertion: there is a risk of misalignment since the molding of its connector is smaller than the shrouding of the bus board connector!
Ensure that the -12V indication at the back matches your bus board indication.
MoDrain old version

Reclaim your unused watts !
Did you know that typical 5V adapters draw 240% of the actual wattage they deliver, with 140% being wasted as heat ?
Moreover they take it from your precious +12V rail.

Beating even other switching-supply adapters, the NoDrain converter takes its power where there is plenty unused: the -12V negative rail ! *
You can safely assume that the current drawn on the 5V adapter will take half as much on the -12V rail.

The NoDrain adapter does its conversion with high efficiency.
With 1 amp available, you can distribute the 5V from the NoDrain to several busboards.
Thanks to ultra high-speed switching technique there is no noise to be heard.

Just plug a NoDrain in one of the connectors at the back of your rack and you’re done.

Do you have this kind of regulator to give you 5V?

Linear regulators are the worst possible option to power a 5V rail.
You can easily recognize them by their heatsink tab.

Every single Watt provided on the 5V rail actually draws 2.4 Watts on your 12V rail ! In other words, when 1 Watt goes to the modules, 1.4 additional Watts are wasted heating your case!

See below how the NoDrain transfers the current consumption from the positive rail to the negative rail while dividing it by two !

Example current draw of a setup using a linear regulator being replaced with a NoDrain
In this example, you get back 400mA on your 12V rail!

Linear   NoDrain
+12V   1500 mA 1100 mA
+5V   400 mA 400 mA
-12V   700 mA 900 mA

The power needs on the 5V rail are typically covered by the unused power available in the negative 12V rail*. All of your +12V power is suddenly available for its dedicated use!
Let’s reclaim a good chunk of power on your +12V rail for more modules!

Linear adapters directly soldered on the backplane - as shown on the picture - can usually be disabled by removing a jumper. This allows adding a NoDrain safely.

*based on stats from 50 randomly selected racks on modulargrid – Feb 2017

... or maybe one of those makes your 5V?

Switched mode power Supply (SMPS) adapters are better than linear regulators, but still. Their conversion efficiency is good, only wasting 10 to 20% in heat, but ...

Trouble is that they draw their current from the rail with the heaviest burden: the +12V rail.
This leaves less +12V power for modules and increases the imbalance between the +12 and -12 rails *.

Example current draw of a setup using a typical switching regulator compared to a NoDrain

+12 to +5
+12V   1500 mA 1300 mA
+5V   400 mA 400 mA
-12V   700 mA 900 mA

This is where the NoDrain regulator comes to the rescue. The power needs on the 5V rail are typically covered by the unused power available in the negative 12V rail.
All of your +12V power is suddenly available for its dedicated use.
Let’s reclaim some power from your +12V rail for more modules!

*based on stats from 50 randomly selected racks on modulargrid – Feb 2017

Do you plan assembling your own Eurorack supply?

The most efficient, lightweight and affordable route for a beefy modular supply is going for an SMPS (Switch Mode Power Supply).
SMPS had - and some still have - a bad reputation because, as with anything else, there are good ones and bad ones.
Cheap and/or old designs could indeed be crappy.
Hopefully, plenty of users have reported perfect satisfaction with many SMPS models.
A quick check with users on modular dedicated forums will help you in selecting a good supply.

By the way, did you realize that most pro-audio equipment these days, including the finest mixing desks, power amps and sound processors, use SMPS?

So where are the issues?
Off-the-shelf affordable SMPS are not inherently designed to fulfill Eurorack needs. When looking for an SMPS providing all 3 required voltages from a single unit, the +12V and -12V rails are typically weak compared to an excessively powerful 5V rail.
These 3-rail supplies are dedicated to computers wherein the 12 volt rails play a secondary role. The 12V rails are not specified with the same care and strength as the “main” 5V rail.
Finally, the cost and weight of such supply block will relate to its hefty 5V power capability, overblown for Eurorack usage.
Better forget the 3-rail supplies!

It’s much easier to find a good two-rail-only +12/-12 SMPS, and not bother for the lack of 5V.
When buying a supply, the first selection criterion is the power available (along with the “cleanness” of the voltages; the smallest the ripple voltage, the better).

In Eurorack, consumption is discussed in milliamps (1 amp = 1000 milliamps), so you have to decide how many amps you need.
Dual supplies offer the same power on both rails. Unfortunately, in practice, there is an imbalance in Eurorack power needs; a typical case will draw almost twice the current on the positive rail than on the negative one*. This is the way the modules are made that creates that consumption imbalance.

Then, we need a 5V rail and the usual way is to put some voltage regulator on the +12V rail.
Knowing that the 12V rail is already the most loaded, doing so is inadequate and to be frank, somehow silly isn't it?
This is where Klavis' NoDrain converter comes handy as it draws its current from the negative rail. The power needs on the 5V rail are easily covered by the unused power on the negative 12V rail. All of your +12V power is then available for its dedicated use.
You don’t have to buy a bigger SMPS to divert some +12V in making the 5V.

*based on stats from 50 randomly selected racks on modulargrid – Feb 2017

Inspiration technology to let you create the difference
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