EyezOn Forum

I plan on purchasing an EVL4 shortly but have a question regarding Auxiliary Power Maximums. I have a Vista 20P control panel with the below auxiliary devices which have a total current draw of 535ma (as stated in the 20P installation manual). Adding a EVL4 at 75ma would bring the total Auxiliary Power draw to 610ma. The Vista 20P documentation states that the Auxiliary Terminal power available is 600ma . This is a residential (non-UL rated) installation.

I think I can make the assumption that the Alpha Keypads would only reach 100ma maximum if the keypad sonalert and the panel backlighting LED lights are activated at the same time. If that is the case I hoping that the extra 10ma overage would only be reached in a worst case scenario.

I'm trying to save having to deal with a second auxiliary power supply and its associated power transformer but want to insure that I'll still be able to access the panel remotely in that worst case scenario.

Does anyone have a comment on what I should do here? Thanks for your help in advance.

Current Devices
(2) 6160 Alpha Keypads (100ma each - total 200ma)
(1) 5881 RF Receiver (35ma)
(1) 4286 Phone Module (300ma)

I have this real handy current/power measuring device call a kill-o-watt. When ever I'm trying to figure out how much power something uses either instantaneously or averaged over time, I plug it into this and read the results right off the meter. My guess would be that you are correct, but I think this would be the easiest way to prove it for sure.

dcuste....
Thanks for reply. Since I posted this message, I decided to just bite the bullet and purchase and install in the additional power supply and associated power transformer. All is up and working as described in the product documentation. Thanks for the suggestion on the Kill-o-Watt. I actually have one of those, but didn't think of using it as I was more interested in the DC side of the power requirement equation. The AC side was not an issue, other than getting the extra power plug space for the second transformer.

The EVL4 is great as it gives me the ability to remote monitor my own system without having to pay the extra monthly rate of a central station. I recognize that I'll have to contact the local law enforcement, but our town is still very responsive, so I don't think I should ever have an issue if the need arises.

dcuste....
Thanks for reply. Since I posted this message, I decided to just bite the bullet and purchase and install in the additional power supply and associated power transformer. All is up and working as described in the product documentation. Thanks for the suggestion on the Kill-o-Watt. I actually have one of those, but didn't think of using it as I was more interested in the DC side of the power requirement equation. The AC side was not an issue, other than getting the extra power plug space for the second transformer.

The EVL4 is great as it gives me the ability to remote monitor my own system without having to pay the extra monthly rate of a central station. I recognize that I'll have to contact the local law enforcement, but our town is still very responsive, so I don't think I should ever have an issue if the need arises.

dcuste wrote:I have this real handy current/power measuring device call a kill-o-watt. When ever I'm trying to figure out how much power something uses either instantaneously or averaged over time, I plug it into this and read the results right off the meter. My guess would be that you are correct, but I think this would be the easiest way to prove it for sure.

Sorry to be a pedant, but that product has an typical accuracy of 0.5% for real-power which means +/-10W. This resolution is useless on a low-voltage system like a security panel as the Envisalink only consumes 0.75W and a Honeywell Keypad consumes 1.35W. You wouldn't be able to tell the difference between 1 keypad installed or 8.

You can only make a useful measurement of power draw on the low-side with a DC current meter and a voltmeter.

K-Man.... Thanks for the info. I kind of suspected that this would be the case, but have never looked up the specs on the Kill-o-watt to see if you could get that fine level of detail. I'm going to make note of these specs for possible future reference.

The other thing that I would have had to simulate while measuring the DC current would be how to activate all devices simultaneously to determine the actual maximum current draw. Since I've already added the auxiliary power supply, I don't think I'm going to take the time to determine what the system's actual draw would be in worst case conditions. I'll have more than sufficient power available after adding the auxiliary power supply.

Thanks to all who have looked and replied to this question.