RTAC86U Power Supply Question

[Jeffrey Young]

I have a quick question about the power supply for the RT-AC86U. On the Asus Website, the power supply specs are listed as;

AC Input : 110V~240V(50~60Hz)
DC Output : 19 V with max. 1.75 A current
DC Output : 12 V with max. 3 A current

I have a couple of 20Vdc, 4A supplies. Has anyone used the 86U at 20Vdc? I suspect that it should not matter, but I do want to make sure.

I'd like to try a larger size supply to see if it makes any difference in the famous router hang on reboot. I have seen read some posts that suggest the current 19V supply may not be able to keep up with the inrush current on startup, thus hanging.

Cheers

 

[OzarkEdge]

I have a quick question about the power supply for the RT-AC86U. On the Asus Website, the power supply specs are listed as;

AC Input : 110V~240V(50~60Hz)
DC Output : 19 V with max. 1.75 A current
DC Output : 12 V with max. 3 A current

I have a couple of 20Vdc, 4A supplies. Has anyone used the 86U at 20Vdc? I suspect that it should not matter, but I do want to make sure.

I'd like to try a larger size supply to see if it makes any difference in the famous router hang on reboot. I have seen read some posts that suggest the current 19V supply may not be able to keep up with the inrush current on startup, thus hanging.

Cheers

I can't say, but it might be prudent to measure that 20vdc to know it's not more than 20vdc.

OE

 

[L&LD]

With a 5% higher voltage over specs, it may be more harmful than helpful, in the long term?

I have not read anything on this forum that corroborates the claim that a 'beefier' adaptor has helped anyone at all with that issue.

 

[Jeffrey Young]

Thanks L. Certainly nothing concrete written about the subject. Have read in other locations that the 86u may be under powered. Trying to find a schematic for the unit. The specs suggest it can work with supplies between 12 and 19Vdc thus I believe it has a DC to dc converter inside for regulation. With that, the unit probably has a higher input tolerance than 19, was just hoping someone could confirm. I would be interested in trying a higher amperage supply just to see if behavior was any different. I have a 20v 4A supply with a 4mm barrel handy to give it a try.

Thanks anyway.

 

[wouterv]

I don't know where you got the 12 V spec from.
The rear of the router and the manual specifies 19 VDC / 1.75A.
Usually those AC adapters have an output voltage higher than what is specified, going over 19 V will at least mean more heat in the router's own voltage regulators.
It is too bad the electronic consumer market has not standardized to one common voltage and common connection, like they try for mobile phones, and no longer automatically supply an AC adapter which every device.
Some weeks ago I finally threw my unused AC adapter collection away, which were about 20 adapters collected over the years from defect devices, with all kind of odd voltages, and not used for many years.

 

[Jeffrey Young]

I don't know where you got the 12 V spec from.

Right from ASUS spec page for the AC86U

It is too bad the electronic consumer market has not standardized to one common voltage and common connection, like they try for mobile phones, and no longer automatically supply an AC adapter which every device.

Amen

 

[wouterv]

Right from ASUS spec page for the AC86U

Ah, the specification page was willing to open again today, and right it shows a dual output. Believe me, that is not correct.
Rely on what is printed on the router label:

 

[L&LD]

The specifications page may be stating what the options are for that specific model (depending on which area of the world you buy it in). The specific model is definitely saying what it needs.

 

[laxdog]

Apologies for digging such an old thread, but I couldn't find any more information on this and wanted to run my AX86U from a power delivery battery bank during planned maintenance on the power grid. This thread is high in search results, so thought I'd update with my findings.

It's been running for 5 hours now at 20v using around 0.3A without any problems.

I used this cable https://www.amazon.co.uk/dp/B07W6ZFJKX/?tag=smallncom-21

 

[miazza]

If it is specified at 19 Vdc this means the all components are rated at least for 25Vdc.
If you are using 20Vdc stabilized , the derating reduction is negligible and so the PS reliability is not affected.

 

[laxdog]

That's interesting, is there a formula or something that can be used to work that out for other voltages, or how did you get to 25V?

My electronics knowledge is limited.

 

[miazza]

There is not a formula.
Normally it is a design rule to apply a derating factor to all the electronics inside a circuit (voltage, current, power and temperature).

A good design rule is to not exceed 75% of the rated parameter.

An more is the derating factor and better is will be the expected reliability of your device.