Battery pack for Rigol DS1054Z

[usagi]

You'll end up with a powerful 48 volt motor too!   Kind of an expensive way to go, but easy.

$180 vs $61. yeah, expensive... 

[McBryce]

What type of battery do commercial battery powered scopes use? Would the battery pack from a Tektronix scope or even something like an Owon be of any use?

McBryce.

[Lightages]

I am beginning to think the NiMH batteries I linked to would be the best bet. The next question is if the SMPS controller chip is up to the task of continuous low voltage input.

[Zero999]

Some interesting suggestions.

I've measured the current and at 50V it's about 440mA, which agrees with Lightages's result, so I didn't bother measuring the current at different voltages.

I'd rather not use an inverter, not only does it take up extra space and use more power but cheap and lightweight inverters tend to be modified sinewave which are noisy and may cause problems with EMI.

A boost converter is better but it's still an additional loss of efficiency/battery capacity.

I prefer the idea of a passive solution. Each battery could be wired to separate contacts on a connector. When the 'scope connector is plugged in, the batteries could be wired in series and when the charger is connected, they could be wired in parallel or individually connected to separate chargers.

It's probably not a good idea to run the 'scope below 40V for long periods of time. I've ran it for awhile on 48V and nothing bad seemed to happen. The oscilloscope didn't run any hotter than normal.

My current set up uses four SLAs, I don't know what capacity but each weigh 2.5kg (so that's 10kg in total). The idea is to replace them with something lighter.

[mikeselectricstuff]

Another potential issue running mains SMPS's on DC is if there is a real on-odd switch - DC ratings of switches are typically much lower due to potentially non self-extingguishing arc issues.

[usagi]

how about bypassing the smps entirely? does the rigol really use 48v internally?

[Lightages]

Unfortunately nobody has done the reverse engineering to make a schematic yet. I haven't poked around inside yet neither. 48V is not any specification, it is just the lower reliable voltage that the power supply will start with.

[Zero999]

One thing I've noticed is there's less mains pick-up when run off a battery. On battery power, I can hold the probe in my hand and I get less than 2V peak to peak but on mains I get ten times that.

[BillW50]

So how are you coming along with this? If I were going to do it, I would opt for 18650 or even 26500 lithium batteries. Although you would need like 12 of them to connect in series to get the voltage you would want. You can buy battery holders, but I never seen one that holds like 12+ or them. Although you could connect smaller ones in series to hold more of course.

You know I too thought of doing the same with my GW Instek GDS-1062A. Although I later decided to opt for a UT81B (a portable scope that runs on four AA batteries instead). Not as good as yours or my other scopes. But it is portable, small, and easy on batteries. I get about 12+ hours straight on my Panasonic Eneloop 1900mah batteries per charge. The average drain is about 125ma @ 6v.

[Zero999]

The plan is to use four 12V batteries (regardless of the chemistry) and wire them to connectors. This should avoid the need for a specialised custom charger as 12V is a fairly common voltage.

I'll probably use two separate connectors, one for the anodes (socket) and one for the cathodes (plug), which will be made to be incompatible with one another to prevent short circuits. The idea is to change the configuration between series and parallel by wiring the connectors on the charger and oscilloscope differently.

I haven't decided what chemistry to use. For now, I'll just stick with the SLAs I have, make the connectors and cables, then I can look into buying some lightweight, higher energy density batteries.

[bitseeker]

The idea is to change the configuration between series and parallel by wiring the connectors on the charger and oscilloscope differently.

Great idea. Ease of use without losing the ability to balance the batteries.

[usagi]

still recommend against using >2 batteries. what a pain to constantly manage a pile of them.

dc boost converters cost almost nothing these days.

[Lightages]

I agree about the battery management being a pain but there are other considerations, such as forma factor and weight. It is easy to get four smaller batteries into a nice flat package to velcro to the back of the case than it is to get a big 12V higher capacity battery that will fit nicely. The 12V one battery has the benefit of being able to use a commonly available external DC source to run the scope too, like a car.

The question still remains if the SMPS IC inside is being over stressed by running at 48V nominal.

[usagi]

bypass the internal ps and find out what real voltage it consumes internally. unlikely it is 48vdc. drill a hole and put a barrel connector.

[Lightages]

There are probably more like 3.3V, 5V, -5V, 9V,12V -12V and maybe more. A simple internal direct DC feed is not going to work.

[mikeselectricstuff]

There are probably more like 3.3V, 5V, -5V, 9V,12V -12V and maybe more. A simple internal direct DC feed is not going to work.

Pretty sure you could check this from Dave's teardown - at the very least establish how many rails there are. you'd need to pull it apart to measure current though.

[usagi]

from the teardown: 6.3V -7.5V 5V5A  -17.5V

internal psu header similar to atx. potential market for someone to make a simple retrofit board for 12v battery powered rigol. similar to this: http://www.amazon.com/Mini-PicoPSU-150-XT-DC-DC-power-supply/dp/B0045WFZSQ

[tautech]

bypass the internal ps and find out what real voltage it consumes internally. unlikely it is 48vdc. drill a hole and put a barrel connector.

And what supplies the LCD backlight?
Not DC.

[Lightages]

Actually, from Dave's tear down photos, 5V at 5A x2, 6.3V x2, -7.5V, 17.5V, -17.5, plus fan supply. As Dave said in his video it would possible to replace the entire power supply with a fully redesigned one with an internal battery. I agree this would be optimal but not cheap. The OP's idea, I believe, is something simple and easy and external so as to not have to hack or replace major components. Four 12V battery packs in series can be done for around $40 plus a charger. Make that $60 for a hack and it is ready to go. Redesign a complete power supply and stuff it inside is going to be a longer process and probably not cheap. Perhaps there is a Kickstarter opportunity for someone here. With enough volume it could be cheaper in the long run than a DIY quick hack. The problem is that it would be mains powered device and need all the relevant certifications. Designing a power supply and battery to stuff inside is not going to be cheaper I would think, if only for a one off or even tens.

Perhaps the idea of a plug in DC-DC converter running from 12V is a good idea. This would circumvent the need for safety certifications and people could use a certified generic power brick for AC use and an external battery for portable use. The problem with this then becomes the loss of AC sync, and hacking the cabinet.

Still, four 12V batteries in series would be the fastest and simplest way at this point. In Dave's tear down I did not see what SMPS chip is being used, but I could be blind or too impatient to watch all of it again.

[tautech]

Actually, from Dave's tear down photos, 5V at 5A x2, 6.3V x2, -7.5V, 17.5V, -17.5, plus fan supply. As Dave said in his video it would possible to replace the entire power supply with a fully redesigned one with an internal battery. I agree this would be optimal but not cheap. The OP's idea, I believe, is something simple and easy and external so as to not have to hack or replace major components. Four 12V battery packs in series can be done for around $40 plus a charger. Make that $60 for a hack and it is ready to go. Redesign a complete power supply and stuff it inside is going to be a longer process and probably not cheap. Perhaps there is a Kickstarter opportunity for someone here. With enough volume it could be cheaper in the long run than a DIY quick hack. The problem is that it would be mains powered device and need all the relevant certifications. Designing a power supply and battery to stuff inside is not going to be cheaper I would think, if only for a one off or even tens.

Perhaps the idea of a plug in DC-DC converter running from 12V is a good idea. This would circumvent the need for safety certifications and people could use a certified generic power brick for AC use and an external battery for portable use. The problem with this then becomes the loss of AC sync, and hacking the cabinet.

Still, four 12V batteries in series would be the fastest and simplest way at this point. In Dave's tear down I did not see what SMPS chip is being used, but I could be blind or too impatient to watch all of it again.

Couldn't you just check the Service manual for the PSU voltages? 
Does it not come with these scopes on the CD along with the User manual?

[pickle9000]

Actually, from Dave's tear down photos, 5V at 5A x2, 6.3V x2, -7.5V, 17.5V, -17.5, plus fan supply. As Dave said in his video it would possible to replace the entire power supply with a fully redesigned one with an internal battery. I agree this would be optimal but not cheap. The OP's idea, I believe, is something simple and easy and external so as to not have to hack or replace major components. Four 12V battery packs in series can be done for around $40 plus a charger. Make that $60 for a hack and it is ready to go. Redesign a complete power supply and stuff it inside is going to be a longer process and probably not cheap. Perhaps there is a Kickstarter opportunity for someone here. With enough volume it could be cheaper in the long run than a DIY quick hack. The problem is that it would be mains powered device and need all the relevant certifications. Designing a power supply and battery to stuff inside is not going to be cheaper I would think, if only for a one off or even tens.

Perhaps the idea of a plug in DC-DC converter running from 12V is a good idea. This would circumvent the need for safety certifications and people could use a certified generic power brick for AC use and an external battery for portable use. The problem with this then becomes the loss of AC sync, and hacking the cabinet.

Still, four 12V batteries in series would be the fastest and simplest way at this point. In Dave's tear down I did not see what SMPS chip is being used, but I could be blind or too impatient to watch all of it again.

Couldn't you just check the Service manual for the PSU voltages? 
Does it not come with these scopes on the CD along with the User manual?

That would be a no. I'm not sure I have ever seen a Rigol service manual or schematic.

[tautech]

Actually, from Dave's tear down photos, 5V at 5A x2, 6.3V x2, -7.5V, 17.5V, -17.5, plus fan supply. As Dave said in his video it would possible to replace the entire power supply with a fully redesigned one with an internal battery. I agree this would be optimal but not cheap. The OP's idea, I believe, is something simple and easy and external so as to not have to hack or replace major components. Four 12V battery packs in series can be done for around $40 plus a charger. Make that $60 for a hack and it is ready to go. Redesign a complete power supply and stuff it inside is going to be a longer process and probably not cheap. Perhaps there is a Kickstarter opportunity for someone here. With enough volume it could be cheaper in the long run than a DIY quick hack. The problem is that it would be mains powered device and need all the relevant certifications. Designing a power supply and battery to stuff inside is not going to be cheaper I would think, if only for a one off or even tens.

Perhaps the idea of a plug in DC-DC converter running from 12V is a good idea. This would circumvent the need for safety certifications and people could use a certified generic power brick for AC use and an external battery for portable use. The problem with this then becomes the loss of AC sync, and hacking the cabinet.

Still, four 12V batteries in series would be the fastest and simplest way at this point. In Dave's tear down I did not see what SMPS chip is being used, but I could be blind or too impatient to watch all of it again.

Couldn't you just check the Service manual for the PSU voltages? 
Does it not come with these scopes on the CD along with the User manual?

That would be a no. I'm not sure I have ever seen a Rigol service manual or schematic.

http://www.siglentamerica.com/support_download_11
What isn't there is currently being prepared for free download access.

[pickle9000]

Actually, from Dave's tear down photos, 5V at 5A x2, 6.3V x2, -7.5V, 17.5V, -17.5, plus fan supply. As Dave said in his video it would possible to replace the entire power supply with a fully redesigned one with an internal battery. I agree this would be optimal but not cheap. The OP's idea, I believe, is something simple and easy and external so as to not have to hack or replace major components. Four 12V battery packs in series can be done for around $40 plus a charger. Make that $60 for a hack and it is ready to go. Redesign a complete power supply and stuff it inside is going to be a longer process and probably not cheap. Perhaps there is a Kickstarter opportunity for someone here. With enough volume it could be cheaper in the long run than a DIY quick hack. The problem is that it would be mains powered device and need all the relevant certifications. Designing a power supply and battery to stuff inside is not going to be cheaper I would think, if only for a one off or even tens.

Perhaps the idea of a plug in DC-DC converter running from 12V is a good idea. This would circumvent the need for safety certifications and people could use a certified generic power brick for AC use and an external battery for portable use. The problem with this then becomes the loss of AC sync, and hacking the cabinet.

Still, four 12V batteries in series would be the fastest and simplest way at this point. In Dave's tear down I did not see what SMPS chip is being used, but I could be blind or too impatient to watch all of it again.

Couldn't you just check the Service manual for the PSU voltages? 
Does it not come with these scopes on the CD along with the User manual?

That would be a no. I'm not sure I have ever seen a Rigol service manual or schematic.

http://www.siglentamerica.com/support_download_11
What isn't there is currently being prepared for free download access.

@ tautech that really deserves a thread of it's own and Siglent should push that info.

[mikeselectricstuff]

bypass the internal ps and find out what real voltage it consumes internally. unlikely it is 48vdc. drill a hole and put a barrel connector.

And what supplies the LCD backlight?
Not DC.

I have never seen a CCFL backlight that's run from a main PSU board in anything other than a TV or monitor - there is always a separate inverter running off one of the DC supplies, most commonly 12V.

[Lightages]

While I agree that Siglent is much more up front with information, I would not call the service manual from Siglent a real service manual. There is a lot of useful information, but no schematics and no parts list. There is not even a block diagram. Like I said, much better than Rigol.