Power supply options - Nevada

[tooth_dr]

Hello all

I currently have a power supply that was produced by Maplin, I got it just before they closed.  It is rated at 3 amps continuous and 5 amps 50%, surge 7 amps.

With the kit that I now plan to run, I'm going to be over the ratings.

I have found the Nevada range in my search, and was considering buying one larger one, rather than another smaller one and then have two power supplies running.  There is redundancy in having two supplies, but I also like the idea of just a single unit.  I will still have the current one as a backup should I need to use it.

Looking at these ones as a stand alone.  Switched power supply or does it need to be linear?

 

https://www.nevadaradio.co.uk/product/nevada-psw-30h/

https://www.nevadaradio.co.uk/product/nevada-ps23-sw1/

 

Any advice regarding the suitability?

 

Alternatively just stick with the one on FLOs website?

https://www.firstlightoptics.com/batteries-powerpacks/nevada-ps-08-6a-8a-regulated-linear-power-supply.html

 

Thanks

Adam.

Edited April 1, 2020 by tooth_dr

[MarkAR]

Easiest thing would be to total up the current draw of all your equipment, if the FLO one at 6amp is enough then that'll do. No idea about the difference between linear and switch mode.

 

[symmetal]

I use switch-mode supplies for all my gear and haven't had any issues with them. Switch-mode supplies generally have more high frequency noise on their output than linear ones though I've found that doesn't cause any issues with astro cameras. I did comparison tests on my Atik CCD running off a switch mode and a leisure battery and there was no difference in the noise output from the camera. As virtually all CMOS cameras are powered from much more noisy USB anyway that isn't an issue. I have the PSW-30H you linked to as a general purpose supply. I also have the Nevada 8A linear and used it for a while but it gets hot even supplying 4A so needs good ventilation. Also on mine the ammeter reading is just a suggestion and reads 2A more than it's actually supplying.

FLO actually sell the Nevada PSW-30  switch-mode as well which is much the same model as the PSW-30H but in a more stylish case and also has variable output voltage too.

Alan

[tooth_dr]

9 hours ago, symmetal said:

I use switch-mode supplies for all my gear and haven't had any issues with them. Switch-mode supplies generally have more high frequency noise on their output than linear ones though I've found that doesn't cause any issues with astro cameras. I did comparison tests on my Atik CCD running off a switch mode and a leisure battery and there was no difference in the noise output from the camera. As virtually all CMOS cameras are powered from much more noisy USB anyway that isn't an issue. I have the PSW-30H you linked to as a general purpose supply. I also have the Nevada 8A linear and used it for a while but it gets hot even supplying 4A so needs good ventilation. Also on mine the ammeter reading is just a suggestion and reads 2A more than it's actually supplying.

FLO actually sell the Nevada PSW-30  switch-mode as well which is much the same model as the PSW-30H but in a more stylish case and also has variable output voltage too.

Alan

Thanks Alan, I didn't see the other PS on FLO.  I don't think I would need the variable voltage, but agree the housing looks better.

 

11 hours ago, MarkAR said:

Easiest thing would be to total up the current draw of all your equipment, if the FLO one at 6amp is enough then that'll do. No idea about the difference between linear and switch mode.

 

I have done a rough calculation of my current draw.

CCD running at 50% power = 2A

EFW = 0.3A

Mount = 1A

Dew Heaters = 2A

I have three cameras/EFWs, so total continuous power draw would be around 11 amps.

 

 

 

[Laurin Dave]

I have the one form FLO running my mount, focusers, dew heaters and a few other bits in my observatory... (but not the camera cooling)   the only downside of variable voltage I have found  is when you accidently turn it on in the dark when its set to 8v...  everything seemed to work fine but I woke to find that both scopes had dewed up..    Took ages to work out what was wrong

[david_taurus83]

I have the 30amp Nevada linear version. Tis a heavy beast and it has a fan for cooling so gets quite noisy. It's by the back window that's left ajar when I run a cable out to the mount. I opted for that one as I had read that the switched supplies can induce noise though that may not be an issue at all. It has variable voltage selection. I wanted that feature as I can increase the voltage if I get too much voltage drop from running through a 15m 1.5mm cable.

[symmetal]

1 hour ago, tooth_dr said:

I have three cameras/EFWs, so total continuous power draw would be around 11 amps.

I don't think you'll be using as much current as that in reality Adam. Dew heaters will be around 1A at full power unless you have a large scope. The mount will consume more when slewing. My dual rig with cameras cooled, plus guide scope, 3 dew heaters via controllers, AZEQ6, mini PC, USB hub, dual auto focusers, consumes about 4.5A in total when tracking/imaging and around 6.5A when slewing in both axis. It all runs from a 100W switch mode which can supply 8.5A. It just runs warm in use. Having extra capacity is always a good thing so the 30A PSU will just be coasting. 😀

Alan

[tooth_dr]

1 hour ago, symmetal said:

I don't think you'll be using as much current as that in reality Adam. Dew heaters will be around 1A at full power unless you have a large scope. The mount will consume more when slewing. My dual rig with cameras cooled, plus guide scope, 3 dew heaters via controllers, AZEQ6, mini PC, USB hub, dual auto focusers, consumes about 4.5A in total when tracking/imaging and around 6.5A when slewing in both axis. It all runs from a 100W switch mode which can supply 8.5A. It just runs warm in use. Having extra capacity is always a good thing so the 30A PSU will just be coasting. 😀

Alan

Cheers Alan.  Thats good to hear.  I have been running a dual rig on my current power supply - it offers 3-5 amps, with 7 amp surg.

The figures I obtained for the cameras are around 1.7-2.0A at 50% power.  I find that mine run anywhere from 45-65% at -20, depending on ambient.  So I was estimating 6A in total for the cameras.  Three dew heaters - I was allowing 0.7A each.  I didnt count the USB HitecAstro hub, and Moonlite motor focuser, and guidecam. I dont know what the mesu draws, but I think it wouldnt be unreasonable to assume around 8-9A total draw?  I just think that the smaller one from FLO would be on the limit?

Edited April 2, 2020 by tooth_dr

[tooth_dr]

1 hour ago, Laurin Dave said:

I have the one form FLO running my mount, focusers, dew heaters and a few other bits in my observatory... (but not the camera cooling)   the only downside of variable voltage I have found  is when you accidently turn it on in the dark when its set to 8v...  everything seemed to work fine but I woke to find that both scopes had dewed up..    Took ages to work out what was wrong

Cheers Dave.  The camera cooling appears to be the big draw.  How do you run your cameras?

[Laurin Dave]

22 minutes ago, tooth_dr said:

Cheers Dave.  The camera cooling appears to be the big draw.  How do you run your cameras?

Hi Adam...  I run them off the power bricks they came with from ZWO and SX... I have plans to connect them all to the PSU via a Powerpole distribution box and tidy up/reduce the number of cables but as it works fine at the moment I've put them on hold, something to do over the summer...  

Dave

 

[tooth_dr]

23 minutes ago, Laurin Dave said:

Hi Adam...  I run them off the power bricks they came with from ZWO and SX... I have plans to connect them all to the PSU via a Powerpole distribution box and tidy up/reduce the number of cables but as it works fine at the moment I've put them on hold, something to do over the summer...  

Dave

 

Thanks Dave. I have a couple of those, Baader 5A. Leads are a bit short on the 12v side, I don’t like anything 240v in the open bit of the shed. 

[Jkulin]

Hi Adam,

I've been using these for 2-3 years now and they are brilliant: -

https://www.nevadaradio.co.uk/product/nevada-psw-30/

Save yourself and buy direct form Nevada.

I have two of them and split the loads, which one powering my laptop and mount and the other powering my gear as I have a 33 metre run and don't want any major drop.

You can just plug them in and forget, never given me an ounce of trouble.

[tooth_dr]

@Jkulin thanks for the input John.  I wasn't sure about the switched versus linear, but obviously you have no issues.

[Jkulin]

Just now, tooth_dr said:

@Jkulin thanks for the input John.  I wasn't sure about the switched versus linear, but obviously you have no issues.

Seriously these are perfect Adam, they just work perfectly with all my kit.

[TerryMcK]

+1

I also have a Nevada switched mode psu which replaced an older non switched mode psu. My rig never draws more than 4 amps at 13.8v. There is a meter on the PSU switchable between current and voltage.

ZWO cooled camera, mount, dew straps x3

[old_eyes]

I am using the Nevada switch mode supply https://www.firstlightoptics.com/power-accessories/nevada-psw-30-25-30a-switch-mode-power-supply.html. Totally stable and reliable. Quiet and cool at the load I am placing on it.

As has been said switch mode supplies can have more noise. As I chase down various noise sources in my rig I have experimented with a separate linear supply for the main camera. However, I think this is may be noise from other devices hanging off the same 12V bus rather than the power supply as when I unplug everything else except the camera there is no noise. This is not definitive by any means. Could be dodgy cable, connector or something else. I will get to the bottom of it as I want to run off one PS if I can.

[tooth_dr]

Thanks for taking time to reply.  Will decide later and get it ordered!

[david_taurus83]

Just bear in mind voltage drop depending on the length and resistance of the cable you will use. At 13.8v output on my PSU I'm reading 12.5v at the mount after 15m length of 1.5mm cable.

[old_eyes]

1 hour ago, david_taurus83 said:

Just bear in mind voltage drop depending on the length and resistance of the cable you will use. At 13.8v output on my PSU I'm reading 12.5v at the mount after 15m length of 1.5mm cable.

Agreed I used heavy duty battery cable for my main run from PS to pier https://www.12voltplanet.co.uk/TWFLEX10MMSIAMESE.html. About 5m run. No measurable voltage drop. It was probably overkill, but I did not want to have to replace power cables in the conduit due to the voltage falling off at the business end.

[FLO]

On 03/04/2020 at 00:30, Jkulin said:

Save yourself and buy direct form Nevada.

You would save 5p ... 🙂

Steve

[tooth_dr]

4 minutes ago, FLO said:

You would save 5p ... 🙂

Steve

Just to update this thread - I havent bought one yet.  I'm using a Baader power supply 240v - 12v 5A to run both QHY9s.  I've the 12v cable run though the wall of the warm room to the QHY9 power packs.  I've decided to save my money for the time being, but once I move to my dome I'll be in the market for a power supply to run all.

 

Cheers

[FLO]

Wasn’t chasing a sale. Honest 🙂

Was only responding to Jkulin’s advice. 

Steve