Powering EnviR & CC128 From A USB Port Suggestion.

[Dominic]

I'm currently running an EnviR & a CC128 Consoles both connected to a
PC 24/7. Now I realise this is not exactly an energy saving scenario
but the PC was already on 24/7 before I became interested in
monitoring my power consumption.

It is such a shame that the USB to Serial Prolific Chipset was not
built into the Currentcost console as this would facilitate powering
the console from the USB also via say a small usb connector like you
would find on a digital camera for or mobile phone for example. The
currentcost could then be supplied with a small USB type wall adaptor
to power it up for none PC users or plugged into the PC.

If any of the current cost developers are reading this I wonder what
the exact power requirements of the console are? It currently runs on
3v but would it handle a 5v supply? If so I will probably power it
from a USB port to save having to use the two wall adaptors. ive not
looked inside the console yet so not sure if there are any voltage
regulators inside?

Cheers Dom

www.gb3dc.co.uk

[Dominic]

----- Original Message -----
From: "Michel lecomte" <michel.a...@gmail.com>
To: "Dominic" <dominic...@gmail.com>
Cc: "Current Cost" <curre...@googlegroups.com>
Sent: Friday, September 10, 2010 8:16 PM
Subject: Re: Powering EnviR & CC128 From A USB Port Suggestion.

> will it make any difference in terms of power use whether you get it
> from the mains plug or the USB? The device (Envi) pulls the same
> amount, no matter where you get it from.

I would imagine I would save around 10-11 watts saving in my situation. The
Envi PSU seems to draw 6 Watts when I measured it using a separate
standalone Watt Meter. That is 6w off load not even connected to the envi.
Just the PSU. So im running two thats is 12w. Now the PC is already on and
the envi is such a low current device I would expect to not actually be able
to detect an increase in power on the PC. My PC pulls between 40-50w
depending on what its doing and when I plug in a USB device I do not see an
increase to be honest.

I always charge my mobile phone, Nintendo DS & MP3 Player from the PC.

12w 24/7 equates to 105 KWh a year if my maths are about right?

Cheers Dom

www.gb3dc.co.uk

[Neko]

USB power depends on the interface and most of these today are version
2.0 with the older version 1.1 and the less than a year old 3.0. The
power available is typically 100mA with a max of 500mA on the USB 2.0
devices for a total power of 2.5Watts. USB 3.0 has increased the
typical power to 150mA and increased the max to 900mA for a total
power of 4.5Watts. The new bridge device coming from Current Cost can
be powered by an AC power supply or from the USB interface which I am
hoping will replace the need for a 24/7 computer device. I think the
Envi and EnviR could be powered by USB based upon the very speculative
lack of heat from the Envi. A portable 2.5inch disk drive can be
powered by USB 2.0 with 2.5 watts and it is much warmer than the Envi.
For more details try the following link and scroll down to the power
section that discusses the power in detail.

http://en.wikipedia.org/wiki/Universal_Serial_Bus

Regards,
Neko

[Michel lecomte]

will it make any difference in terms of power use whether you get it
from the mains plug or the USB? The device (Envi) pulls the same
amount, no matter where you get it from.

2010/9/10, Dominic <dominic...@gmail.com>:

--
Michel LECOMTE

[Neko]

I would expect a dedicated USB power supply will probably be more
efficient than the PC power supply due to the poor efficiency of
switching power supplies at low power levels. The Apple iPhone power
supply is an example of a small but efficient power supply.

On Sep 10, 12:16 pm, Michel lecomte <michel.a.leco...@gmail.com>
wrote:

> will it make any difference in terms of power use whether you get it
> from the mains plug or the USB? The device (Envi) pulls the same
> amount, no matter where you get it from.
>

> 2010/9/10, Dominic <dominic.caul...@gmail.com>:

[Dominic]

On Sep 15, 8:27 am, Neko <keithmclau...@gmail.com> wrote:
> I would expect a dedicated USB power supply will probably be more
> efficient than the PC power supply due to the poor efficiency of
> switching power supplies at low power levels. The Apple iPhone power
> supply is an example of a small but efficient power supply.

That assumption is 100% correct. Although Switch Mode PSU's are more
efficient then Analogue Transformer PSU's in general. So an Apple
charger is probably very efficient as it is the correct size for the
job & is switch mode. The Current cost PSU is SMALL but analogue.

In my case the Computer is already in use up and running using 50w or
so. The additional load by running the current cost from the PC USB
port is so low that I can not detect any power increase on the Primary
side of the PSU. Still 50w.

The TWO current cost PSU's I am now no longer running were pulling
about 12w together from the mains so for the sake of a usb lead and a
couple of diodes to reduce the 5v nearer to the 3v needed I have a
saving of 12w.

I hope this makes sense. Cheers Dom

[yellowpark]

You can power an Envi using the serial pins on the RJ45 socket used by
the cable. So this is possible. And it would possibly work with a
simple cable mod.

[Dominic]

That is very useful info. So I might be able to feed the 5v line from
within the Prolific USB Dongle/PLUG up the same lead and into the
RJ45.

Do you know the exact DC requirement of the Envi? I've not looked
inside but I am guessing a "Microchip PIC" uP is at the heart of it?
Would it handle 5v DC or do I need to drop it to 3v? Maybe a couple of
diodes in series with the 5v line to drop it 1.4v

I will have a look into this. Does this mean the "Bridge" can power
the console also the same way?

Any news on the Com Port Option yet?

Cheers Dom

[Rich]

To half answer your question the bridge can power the Envi, I just got
my bridge today and it's a slightly different design to what's been
talked about.

It's got an RJ45 for ethernet, a power socket for the adapter and a
RJ11 style connector that goes to the Envi's serial port. If you
unplug the power to the Envi once the serial cable from the bridge is
attached it stays powered.

Rich