Power Drain

[jdkmunch]

Stayout - I now have two bulbs hooked up to a 12V 1000mA transformer.  That should keep it happy.   

Looks like the electric savings is going to be minimal.

[stayouttadabunker]

You must of put the negative wire onto the 12V live wire to fry it...
You can't be doing that with dc voltage!

I was modifying my post while you guys posted.
Take a look at my power supply amperage readings.

[jdkmunch]

okay,
I decided to plug it into my benchtop DC power supply which has an ampmeter on it.
With one bulb at 12Vdc ,the inverter draws just over 400mA.
With two bulbs on the inverter, it draws over 600Ma.
Logisys specs on the packaging is way off.
Look at these pictures from my power supply needles>>>

-  Thanks for the time to check this  !!

[poppo]

okay,
I decided to plug it into my benchtop DC power supply which has an ampmeter on it.
With one bulb at 12Vdc ,the inverter draws just over 400mA.
With two bulbs on the inverter, it draws over 600Ma.
Logisys specs on the packaging is way off.
Look at these pictures from my power supply needles>>>

That came pretty close to my guess. 

[jdkmunch]

How can they get away with such inaccurate information on the package?

[poppo]

How can they get away with such inaccurate information on the package?

It's not wrong if it is the tube current. But it is misleading. 

[stayouttadabunker]

I wish my BK Precision Bench Top PS station had digital readings rather than the old needles...

[brichter]

I'm not even sure it's that misleading, as the current spec is listed directly under the output voltage of the inverter, which would lead me to believe the current measurement was made on the output side as well.

If the draw was listed directly under the input voltage, I would assume the draw was measured on the input side as well.

[brichter]

I wish my BK Precision Bench Top PS station had digital readings rather than the old needles...

Why? My PS does have digital readout, but only .1 resolution.

[poppo]

I wish my BK Precision Bench Top PS station had digital readings rather than the old needles...

You should post those findings in the other thread, or link to this one since it does change a lot of assumptions in the other one.

[stayouttadabunker]

I'm wondering about something...
If I add voltage, for example 13Vdc, would the amperage draw be lower?

I just found out something...I put 10 volts on the PS and it only draws just over 500Ma.
Yet, the tubes appear to be just as bright.

When I put 15 volts into it, it draws about an extra 100mA.

These were done with 2 tubes attached.

[poppo]

I'm not even sure it's that misleading, as the current spec is listed directly under the output voltage of the inverter, which would lead me to believe the current measurement was made on the output side as well.

If the draw was listed directly under the input voltage, I would assume the draw was measured on the input side as well.

I agree, but how many people really know which is which? If only one current value is given, the average Joe would think it was talking about the whole unit. In the other thread, even though I thought it was low, I assumed it was the total current, and I'm a tech guy. But without one in my hands, I had no way to actually check it.

[poppo]

I'm wondering about something...
If I add voltage, for example 13Vdc, would the amperage draw be lower?

Short answer is no. However, depending on what the load is, it may. Current=voltage/resistance. So if the voltage goes up, the current goes down. But most circuits are not simply resistive, so depending on what is being powered, as voltage goes up, so may the level of smoke.  

[poppo]

I just found out something...I put 10 volts on the PS and it only draws 500Ma.
Yet, the tubes appear to be just as bright.

When I put 15 volts into it, it draws about an extra 100mA.

The inverter is probably regulated and anything over it's 'nominal' voltage will just be dissipated as heat and hence the extra 100ma with no increase in brightness. And once you reach a certain brightness level, the human eye does not notice subtle changes.

[stayouttadabunker]

I agree..I couldn't really tell the "brightness" without a photographer's light-meter in my hand.
Let's just say it would be "good enough"?    lol
I posted a couple of more pics and readings from 10 and 15 volts above ^^^

[poppo]

I agree..I couldn't really tell the "brightness" without a photographer's light-meter in my hand.
Let's just say it would be "good enough"?    lol
I posted a couple of more pics and readings from 10 and 15 volts above ^^^

That is good info though as there is no sense in over-driving them for no perceivable increase in brightness and only end up using more power. However, 12V supplies are going to be a lot more common than a 10V one.

[stayouttadabunker]

Yeah...when I adjusted the benchtop power supply to the other popular 9Vdc, they were pretty dim.