Today's Message Index:
----------------------
1. 04:13 AM - Re: Cheap bench supply? (C&K)
2. 07:49 AM - Re: Cheap bench supply? (Richard Girard)
3. 02:08 PM - Re: A brown-out alternative? (zwakie)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Cheap bench supply? |
One can usually replace the analog current potentiometer with a multi
position rotary switch and fixed resistors if preferred. I find that
about 6 positions suits my bench supply just fine.
Ken
On 10/12/2018 3:29 PM, Charlie England wrote:
>
>
> On Tue, Nov 13, 2018 at 4:59 PM Charlie England <ceengland7@gmail.com
> <mailto:ceengland7@gmail.com>> wrote:
>
> Anyone have experience with the recent ebay offerings for cheap
> lab supplies? Example below. I tried searching my old AEC emails,
> but the most recent reference I found was for a much more
> expensive model. It'll get minimal use; just final checkout of my
> project's wiring and then rare uses after that, so don't want to
> spend $hundreds.
> 0-30v/0-10a bench supply
> <https://www.ebay.com/itm/10A-Digital-DC-Power-Supply-Variable-Adjustable-Lab-Bench-Test-Equipment-Tool/202435783331?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649>
>
> Thanks,
>
> Charlie
>
>
> Well, I said I'd publish a pirep once I received the unit, so here we go.
>
> The unit seems to work just fine, with a couple of 'idiosyncrasies'.
> The controls are analog, as you'd expect from the pairs of coarse &
> fine adjustment knobs. The only frustrating thing is that current
> limit is set by setting voltage to some reasonably low value, setting
> current to minimum, shorting out the+ & - terminals, and then dialing
> up the current knobs to the desired limit. Then remove the short and
> connect your load. At loads less than the current set point, the
> voltage display shows your set point voltage (actual output voltage).
> The current display will vary between zero and the current set point,
> depending on actual load. Once the current limit is reached, voltage
> (and the displayed voltage, of course) falls to limit current to the
> preset level.
>
> Behavior of the supply is as expected, but it is frustrating to not
> see the actual current limit set point while in operation, until you
> actually hit the limit. Since the knobs are unmarked, this requires
> going back through the limit setting for each new work session, unless
> you trust that the current limit knobs haven't been touched since the
> last session. The ideal supply would have both set point and output
> displays, but for my limited needs, I don't need to pay for ideal. :-)
>
> Assuming long term survival, I consider it a great value compared to
> the $hundreds required for lab grade supplies.
>
> Charlie
>
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon>
> Virus-free. www.avast.com
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link>
>
>
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Cheap bench supply? |
Get some number transfers so you can set the knobs to the same settings you
require. Set the top to 11 and watch "Spinal Tap" for a giggle. :-}
Rick
On Tue, Dec 11, 2018 at 6:18 AM C&K <yellowduckduo@gmail.com> wrote:
>
> One can usually replace the analog current potentiometer with a multi
> position rotary switch and fixed resistors if preferred. I find that
> about 6 positions suits my bench supply just fine.
> Ken
>
> On 10/12/2018 3:29 PM, Charlie England wrote:
> >
> >
> > On Tue, Nov 13, 2018 at 4:59 PM Charlie England <ceengland7@gmail.com
> > <mailto:ceengland7@gmail.com>> wrote:
> >
> > Anyone have experience with the recent ebay offerings for cheap
> > lab supplies? Example below. I tried searching my old AEC emails,
> > but the most recent reference I found was for a much more
> > expensive model. It'll get minimal use; just final checkout of my
> > project's wiring and then rare uses after that, so don't want to
> > spend $hundreds.
> > 0-30v/0-10a bench supply
> > <
> https://www.ebay.com/itm/10A-Digital-DC-Power-Supply-Variable-Adjustable-
Lab-Bench-Test-Equipment-Tool/202435783331?ssPageName=STRK%3AMEBIDX%3AIT&
_trksid=p2060353.m1438.l2649
> >
> >
> > Thanks,
> >
> > Charlie
> >
> >
> > Well, I said I'd publish a pirep once I received the unit, so here we g
o.
> >
> > The unit seems to work just fine, with a couple of 'idiosyncrasies'.
> > The controls are analog, as you'd expect from the pairs of coarse &
> > fine adjustment knobs. The only frustrating thing is that current
> > limit is set by setting voltage to some reasonably low value, setting
> > current to minimum, shorting out the + & - terminals, and then dialing
> > up the current knobs to the desired limit. Then remove the short and
> > connect your load. At loads less than the current set point, the
> > voltage display shows your set point voltage (actual output voltage).
> > The current display will vary between zero and the current set point,
> > depending on actual load. Once the current limit is reached, voltage
> > (and the displayed voltage, of course) falls to limit current to the
> > preset level.
> >
> > Behavior of the supply is as expected, but it is frustrating to not
> > see the actual current limit set point while in operation, until you
> > actually hit the limit. Since the knobs are unmarked, this requires
> > going back through the limit setting for each new work session, unless
> > you trust that the current limit knobs haven't been touched since the
> > last session. The ideal supply would have both set point and output
> > displays, but for my limited needs, I don't need to pay for ideal. :-)
> >
> > Assuming long term survival, I consider it a great value compared to
> > the $hundreds required for lab grade supplies.
> >
> > Charlie
> >
> > <
> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_
campaign=sig-email&utm_content=webmail&utm_term=icon>
>
> > Virus-free. www.avast.com
> > <
> https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_
campaign=sig-email&utm_content=webmail&utm_term=link>
>
> >
> >
>
===========
===========
===========
===========
===========
===========
>
>
--
=9CBlessed are the cracked, for they shall let in the light.=9D
Groucho Marx
<http://www.goodreads.com/author/show/43244.Groucho_Marx>
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: A brown-out alternative? |
I received the last bit today (DC/DC converter) and had some time to kill this
evening, so I built the circuit and tested it successfully on the bench.
I used a Ripca 2152C for the relay and this little critter as the buck-boost converter: https://www.ebay.ca/itm/6-35V-to-1-35V-DC-DC-Buck-Boost-Charger-Power-Converter-Module-With-AluminumSG-/123523715069?oid=112837380675 , along with the diode(s) previously recommended.
It will be a little while before I reach the point with my panel upgrade to glass
before I can confirm it really prevents a brownout. I will report back when
the time comes (hopefully in 2-3 weeks from now).
--------
Marcel Zwakenberg
Europa XS TG || 912ULS || PH-SBR
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=486241#486241
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|