250W lamp replacement by?

[coucou789456]

Good evening

at France-lampes, Mercury Vapor Lamp 250w 4100K for 9€ HT, in E40 base.

francelampes.com/pro/catalog/product_info.php?products_id=5625

there is also this metal halide E40 MXR 175w /WDL BU (discharge lamp, so with a ballast, if your previous lamp had one installed)

jeff

[Clay]

Otherwise in E40 I found this starled.fr/produit.php?prod=111&numr=10

Why is it so expensive? (They don't even do wholesale prices!!!)

Maybe we should fall back on this one
francelampes.com/pro/catalog/product_info.php?products_id=152155

?
...

[coucou789456]

re

it is a discharge lamp, so there must be a ballast

and it's orange in color

if you want a whiter color, you must have at least 3500K

jeff

[Clay]

re

it is a discharge lamp, so there must be a ballast

All Sodium lamps require a ballast?

Can you explain to me what is a ballast (role) I do not find myself there so much!

and it's orange in color
if you want a whiter color, you must have at least 3500K

I don't really have a color criterion!

I simply ask if this change risks completely altering the quality of the lighting that I obtain with current lamps (250W). (Because in terms of power, luminous flux and price, this choice (sodium) looks attractive ).Give me your opinion from this point of view...

[coucou789456]

Hello

Low pressure sodium vapor lamps
This type of lamp is the most efficient type of discharge lamp, producing up to 200 lumens/watt, but at the expense of very poor color rendering. Near-monochromatic yellow light is only acceptable for street lighting and similar uses.

this type of lamp works like the fluorescent tubes that one puts at home with a transformer and a starter, currently replaced by a ballast plate which replaces the 2 previous elements.

jeff

[elephant]

Clay said:

Can you explain to me what is a ballast (role) I do not find myself there so much!

In a discharge lamp, you cause a current to flow through a gas, for example sodium or mercury vapor at low pressure.
This gas is a good conductor.

So, to avoid causing a short circuit, it is necessary to limit the current (intensity) which crosses the lamp. One could imagine putting a resistor in series (I = E/R) but this would be too expensive and would dissipate a lot of energy (W = R.I²); We therefore use a series choke or an electronic circuit (too often less reliable)

[Clay]

Re.

How much (power) does a ballast consume for a 70W lamp?

[Clay]

So, to avoid causing a short circuit, it is necessary to limit the current (intensity) which crosses the lamp.

Why this is not the case for mixed lamps (incandescent mercury)

[elephant]

???? Are you teaching me something or are you mixing everything up?

[Clay]

???? Are you teaching me something or are you mixing everything up?

I was just wondering why the mixed lamps did not need ballasts unlike those with Sodium, why these are likely to be short-circuited?