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Rainman7
04-14-2012, 06:45 AM
A few years back I installed a unique 24v system on a property due to distance issues. It has been working very well except now the cust wants some lighting down his 400' driveway. I want to use led's which operate between 10 & 17 volts. I have a spare branch off a hub to the furthest point we have lit which I connected it to thinking the voltage drop matpy take care of it but it doesn't...only goes down to 21v. Anyone have an idea how I can bring it down?

Lite4
04-14-2012, 06:59 AM
Unique makes a "voltage de-hancer" you wire in line for this purpose. I have attached a link to a former thread on this topic:

http://www.lawnsite.com/showthread.php?t=334512&highlight=voltage+regulator

INTEGRA Bespoke Lighting
04-14-2012, 08:37 AM
I would recommend that you ensure the long term operating voltage of those LEDs falls into the middle of their range and not at the top of the range.

This is the first thing I have heard about Unique's 24V "system" in some time. I guess Nate had it wrong when he predicted that 'this LED thing isn't going to go anywhere'. (paraphrasing)

In the long run, I think it would be better to discuss a complete switch over and update to LEDs for your client. This would require a new transformer and a bunch of retrofit LED lamps or new LED fixtures. Having a mixture of 24V lamps and LED product in the same system is not an ideal long term solution.

steveparrott
04-15-2012, 11:32 AM
A few years back I installed a unique 24v system on a property due to distance issues. It has been working very well except now the cust wants some lighting down his 400' driveway. I want to use led's which operate between 10 & 17 volts. I have a spare branch off a hub to the furthest point we have lit which I connected it to thinking the voltage drop matpy take care of it but it doesn't...only goes down to 21v. Anyone have an idea how I can bring it down?

I wouldn't recommend any of the voltage regulator devices that operate at the fixture - they have a troubled history.

The CAST LED Bullet (http://www.cast-lighting.com/products/fixtures/led-landscape-lighting-fixtures/223/) and Tree Light (http://www.cast-lighting.com/products/fixtures/led-landscape-lighting-fixtures/222/) operate up to 28.8V.

GreenLight
04-16-2012, 09:48 AM
Have you already built this run yet and how many leds/watts are you ultimately going to be pulling off the hub branch?

If you are at 21 volts, empty load from the hub output and you still need to run somewhere from 100-200 feet of wire with 6-8 new leds averaging 3-5 watts per, you could simply use much lower guage wire to exit the hub. For instance, if you came out with 16-18 gauge wire and connected a total of 40-50 watts over the span of a few hundred feet, you can dramatically drop your voltage from that point. You would probably have to avoid daisy chaining because the first few lights would probably still run to hot, but if you made hybrid Tee's that carry multiple lights from a single junction point it's quite feasible.

steveparrott
04-16-2012, 10:08 AM
Have you already built this run yet and how many leds/watts are you ultimately going to be pulling off the hub branch?

If you are at 21 volts, empty load from the hub output and you still need to run somewhere from 100-200 feet of wire with 6-8 new leds averaging 3-5 watts per, you could simply use much lower guage wire to exit the hub. For instance, if you came out with 16-18 gauge wire and connected a total of 40-50 watts over the span of a few hundred feet, you can dramatically drop your voltage from that point. You would probably have to avoid daisy chaining because the first few lights would probably still run to hot, but if you made hybrid Tee's that carry multiple lights from a single junction point it's quite feasible.

It would only take a few burnouts of the incandescent lamps to bring your voltage too high. The risk of over-voltage at the LED's (and subsequent failed LED's) is too great in all these approaches. Either spec LED fixtures that will handle the voltage or run a new line to the transformer.

GreenLight
04-16-2012, 10:20 AM
I agree, it's definitely less than conventional and would have a downside if you had unmonitored halogen burnouts.

INTEGRA Bespoke Lighting
04-16-2012, 09:07 PM
Or you could install a new, conventional transformer and replace all of the 24V lamps with LED lamps. This solution would be much less expensive than replacing all of the fixtures with LED fixtures that have relatively high input voltages.

irrig8r
04-16-2012, 09:56 PM
Well, I'm not going to take sides while the two forum sponsors battle this one out... except to say that I think Steve's solution might work well for you in your situation. It seems that the folks at CAST saw a niche (systems with higher voltage output transformers that CAST, Unique and even Vista were pushing just a few short years ago) and found a way to fill it.

Either way, run the numbers and see which is the most economical or most profitable, depending on your relationship with your client.

S&MLL
04-16-2012, 10:55 PM
Well, I'm not going to take sides while the two forum sponsors battle this one out... except to say that I think Steve's solution might work well for you in your situation. It seems that the folks at CAST saw a niche (systems with higher voltage output transformers that CAST, Unique and even Vista were pushing just a few short years ago) and found a way to fill it.

Ethereal way, run the numbers and see which is the most economical or most profitable, depending on your relationship with your client.

Great advice.
Only thing i could add is watch for color temps. I have never even seen a 24volt install but at what volt do these lamps run warm. If 21 volts is similar to 10.5 on a 12 casts led might appear a bit on the hot side.
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steveparrott
04-17-2012, 08:58 AM
Great advice.
Only thing i could add is watch for color temps. I have never even seen a 24volt install but at what volt do these lamps run warm. If 21 volts is similar to 10.5 on a 12 casts led might appear a bit on the hot side.
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Unlike incandescent lamps, LED's (of all manufacturers) maintain a fairly constant color temp throughout their acceptable voltage range.

steveparrott
04-17-2012, 09:13 AM
...It seems that the folks at CAST saw a niche (systems with higher voltage output transformers that CAST, Unique and even Vista were pushing just a few short years ago) and found a way to fill it.


The main reason we widened the voltage range on our LED's was to allow installers to put more fixtures on single wire runs. The savings in wire cost and labor are huge.

S&MLL
04-17-2012, 01:06 PM
I was reffering to his 24 volt lamps steve. If they are running warm your led might not match color temp
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LLC RI
04-18-2012, 08:42 AM
I agree with James. You're barking up the wrong tree trying to 'make' a non conforming system compatible indefinitely with new technology that is designed for conventional lighting systems.

As an upside to this, by converting to standard 12 volt LED, you can now achieve the long distances you need to go without as much worry about voltage drop, as the LED's are not as 'fussy' as halogen bulbs.

As an aside for all the 'tecchies' out there, IF one were to install an inductive load dimmer ahead of that 24 volt transformer, would the resulting outcome be a lower tap voltage?

George

Rainman7
04-23-2012, 05:59 PM
Well, the unique voltage dehancer supposedly never made it to the shelves. Think I'll just add a transformer and sequencer