LED Nav lights

Cornishman

Cornishman

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I have recently see an advertisement in a French yachting mag for LED navigation lights. It is claimed they are much brighter than the conventional ones, and that a tricolour lamp consumes power at 9 watts.
Anybody got any, or seen any?
 
LED Nav lights can be brighter and certainly draw far less power, however beware of LEDs who's light is then filtered to get a tri or bi colour effect.

I am ready to be corrected, but as it stands, seperate LEDs are required for each colour in order to get a really good quality of light.
 
I saw them side by side with traditional bulb lights at the recent Dublin boat show. Damn things nearly blinded me, much more powerful, but electrical draw etc. I couldn't tell you.
 
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however beware of LEDs who's light is then filtered to get a tri or bi colour effect.

[/ QUOTE ] You're absolutely right. Just ordered an LED from ultraleds and it had to be 'warm white' for the masthead tricolour, not pure white which is the one with the harsh blueish light in early generation cabin LED's. It cost an extra £14 but at under £30 for the bulb and £20 for the masthead unit it made a damned cheap unit. Plus it draws about 1amp with an equivalent output to a 30w fillament bulb.
 
I am considering LED tricolor for my boat...bulb has gone anyway so somebody has to go up there. Bit pricet at over £200.00, yours sounds a lot cheaper....where from?
 
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I am considering LED tricolor for my boat...bulb has gone anyway so somebody has to go up there. Bit pricet at over £200.00, yours sounds a lot cheaper....where from?

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The Lopolight one is a sealed unit guaranteed for 50,000 hours with a built in voltage regulator. The Ultraleds is a bulb which plugs in as a direct replacement inside the tricolour light housing and does not, AFAIK, have a built in regulator.
 
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reduces the amperage used overnight from around 28 amps

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Blimey! That's a 340W bulb at your masthead?!

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Unless we are talking total amps, rather than amp hours...

Myself, I quite fancy a 340W anchor light
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I am considering LED tricolor for my boat...bulb has gone anyway so somebody has to go up there. Bit pricet at over £200.00, yours sounds a lot cheaper....where from?

[/ QUOTE ] I got the masthead tricolour from a boat jumble - new but jumble stock. The LED bulb does have a regulator in it.

I love the lopolights, but it's all a matter of priorities. I could have an LED masthead tricolour for less than £60 or the real deal for £280. £220 is a heck of a difference!
 
Sorry, I know I am being pedantic. But there is opportunity for genuine confusion when people say amps when they mean amp hours. They are quite different things.

And

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Unless we are talking total amps, rather than amp hours...


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The Ultraleds is a bulb which plugs in as a direct replacement inside the tricolour light housing and does not, AFAIK, have a built in regulator.


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It has a driver circuit which maitains a constant light output over the specified voltage range. Details are on the ultraleds website.

The Dr leds one is suitable for a wider voltage range but draws more current. I think I've got the two the right way round. It all on the respective websites anyway
 
I'm guessing that Malthouse meant using red or green LEDs rather than a white one which passes through a red or green filter. The latter work of course by subtracting the othe wavelengths from the light actually emitted by the LED, so make it dimmer/less efficient.
 
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2.4amps per hour.

[/ QUOTE ] An amp is an amp. (actually an abreviation for ampere)

A 25watt 12 volt bulb will pass a current of just over 2 amps more precisely it is 25 ÷ 12 which equals aprox 2.08 amps. No per hour about it just amps.

If a long cable introduces additional resistance into the circuit then the current will actually be less

Ampere hours (Ah) is the product of current in amps and time in hours ie amps x hours.

Thus a 25 watt bulb (passing a current of 2.08 amps) for 10 hours will draw 2.08 x 12 = 20.8 Ah (or 25 Ah in 12 hours)

The Ampere hour is usually only used in relation to battery capacity and is useful in comparing the consumption of electrical equipment over periods of time with the total battery capacity although battery capacities are somewhat dependent on the rate of discharge

The definitions of the various electrical units are:

Ampere; A current of 1 ampere flowing in two parallel conductors 1 metre apart in a vacuum would produce a force between those conductors of 2 x 10^-7 (ie 0.0000002 ) Newtons per metre length. (pretty unhelpful for practical purposes)

Volt: The unit of potential difference (pd) or electromotive force (emf) such that the pd across a conductor is 1 volt when 1 ampere in it dissipates 1 watt of power (a watt is defined as 1 joule per second or 10^7 ergs per second) Also pretty meaniless for practical purposes

Ohm: The unit of resistance such that 1 ampere flowing through a resistance of 1 ohm produces a pd across it of 1 volt.

So the definitions of the amp and the watt are the basics and from those we get

watts = volts x amps

volts = ohms x amps

It is also useful to simplify calculations involving watts to remember that watts =amps² x ohms or watts = volts² ÷ ohms
 
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