Author Topic: DP832 for split rail supply  (Read 364 times)

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Offline netdudeuk

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DP832 for split rail supply
« on: July 01, 2018, 10:23:16 pm »
Hi

Rigol states 'must use wire rated for 9A or greater to prevent damage or a possible fire hazard'.  That's 12 AWG.

https://rigol.desk.com/customer/en/portal/articles/2285140-how-do-i-connect-the-dp832-to-achieve--30v-on-channel-1-and-channel-2-

That seems to fit in with the 3A per channel maximum but if the project is only a lower current one, wouldn't it be ok to use, say, 18AWG wire ?

Thanks
 

Offline Ian.M

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Re: DP832 for split rail supply
« Reply #1 on: July 02, 2018, 12:32:40 am »
They are being over-cautious.  However if you ignore their recommendation, use thin wire, short it at max current and as a result mar the front panel or melt a notch in a binding post insulator, you are S.O.L. 
 
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Offline netdudeuk

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Re: DP832 for split rail supply
« Reply #2 on: July 02, 2018, 02:10:13 am »
They are being over-cautious.  However if you ignore their recommendation, use thin wire, short it at max current and as a result mar the front panel or melt a notch in a binding post insulator, you are S.O.L.

I've located some ring mains cable to I'll use some of that.

Thanks.
 

Offline bson

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Re: DP832 for split rail supply
« Reply #3 on: July 03, 2018, 02:35:40 am »
You don't need to handle more current than the total CC you set.  For example 50mA each on the rails and 150mA on the digital section will need at most 250mA.  And you should set CC limits; this is what will save your projects when you do something stupid.

Just your typical lab 4mm banana jack equipped patch cables are fine, like basic Pomona ones.  Pomonas specifically are rated to 20A.
 

Offline Ian.M

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Re: DP832 for split rail supply
« Reply #4 on: July 03, 2018, 04:03:33 am »
Personally, I'd get some stackable 4mm plugs and make up some short jumpers - 6" between plugs would be a convenient length.   Alternatively, if you rarely use the binding posts to clamp wires, make up custom jumpers for each configuration with crimped fork terminals, with multiple ends depending on the number of terminals you need to tie.
 

Online Hero999

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Re: DP832 for split rail supply
« Reply #5 on: July 03, 2018, 06:19:02 am »
You don't need to handle more current than the total CC you set.  For example 50mA each on the rails and 150mA on the digital section will need at most 250mA.  And you should set CC limits; this is what will save your projects when you do something stupid.

Just your typical lab 4mm banana jack equipped patch cables are fine, like basic Pomona ones.  Pomonas specifically are rated to 20A.
Can the constant current mode be relied on for protection against fire though? Is there a failure mode which could result in the full current being delivered in to a short circuit?

My advice would be don't worry, the CC mode should be reliable enough, but I wouldn't leave it running, unattended.
 

Offline netdudeuk

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Re: DP832 for split rail supply
« Reply #6 on: July 03, 2018, 06:57:09 am »
You don't need to handle more current than the total CC you set.  For example 50mA each on the rails and 150mA on the digital section will need at most 250mA.  And you should set CC limits; this is what will save your projects when you do something stupid.

Just your typical lab 4mm banana jack equipped patch cables are fine, like basic Pomona ones.  Pomonas specifically are rated to 20A.
Can the constant current mode be relied on for protection against fire though? Is there a failure mode which could result in the full current being delivered in to a short circuit?

My advice would be don't worry, the CC mode should be reliable enough, but I wouldn't leave it running, unattended.

My goodness. Is it that bad ?  I have a nearly £500 lab power supply and I can't leave it hooked up ?

Is this because we're talking all three rails here with the (pretty small) potential for the whole 9 amps to be dissipated ?

Would this apply to other PSUs too ?

I'll add that I did set up CC as suggested but at even lower levels.

Thanks

« Last Edit: July 03, 2018, 07:04:26 am by netdudeuk »
 


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