480VAC Indicator Panel LED

[Robert Reed]

To add to Lemps Suggestion, some of these neons come in quite large sizes with well over 1/2" bases making them quite visible from a distance.

[MrAl]

Hi there,

I used to like Neons too, until i found out that after a while they
burn out or something and then start blinking on and off which
gets annoying. If i have the choice now i'll always use LEDs driven
at the proper current for long life over neons.

How hard is it to connect an LED and dropping resistor?
You can also use a high brightness LED and lower the current
which makes the required resistor power rating lower.
For example, you can drive a high brightness LED at 2ma and
still get plenty of light to function as an indicator only, and the
required power rating of the resistor would only be 2 watts when
run from a 500v supply (actually the resistor power is 1 watt with 100
percent safety margin which makes it 2 watts). You can even get
5 watt units for around half a dollar on the web. So, one 250k resistor
and one high brightness LED with the color of your choice (red, yellow,
green, blue, white, white with any color lens).

At 2ma the LED would probably last for 50 years.

[Lenp]

Here is a line voltage 'indicator' that will fill the bill!

http://marsh.ooi.net/Diversified/UPA-130_series.htm

[reloadron]

Here is a line voltage 'indicator' that will fill the bill!

http://marsh.ooi.net/Diversified/UPA-130_series.htm

Additionally ATC (Automatic Timing & Controls) makes a few other canditates. Allied Electronics carries their line.

The first link is the UPA-100

There is also their SLA-440-ALE and the SLU-100-ASA which are relay output devices for phase loss or if a phase dips below a set point.

Ron

[David9]

I forget who the original manufacture was (I think it was Fairchild) of the MID400, but I remember from the data sheet both Voltage and current monitor using this opto isolation chip. The out put is +5 V and could be set up for I/O to a computer system or you could just used normal LEDs to let you know that it working properly. Here is what I found for a data sheet on this: http://www.fairchildsemi.com/an/AN/AN-3007.pdf .
I think it would work for your problem. Take a look
DW

[jollyrgr]

I should close out this topic.

The only viable solution was to use step down transformers and LED indicators for a lower voltage. It was not my first choice but it works great. Instead of putting the lights in the bypass panel as is done traditionally, we mounted the transformers and LEDs in a box mounted to the side of the bypass panel. If I remember, I will take a picture of the system and post it.

[MrAl]

Hi again,


Sounds kind of expensive just for indicator lights though,
and transformers are not the best long term solution either.

Resistors last for years and years so i cant see why they didnt
use resistors in series with LEDs or something of that sort.

[Lenp]

"If I were doing this for myself I would use a wall wart and low voltage LEDs......This cannot be a "home brew" item or I'd not even have posted.

Hummm!

Len