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Necessity of relays for HID's?
Thread Starter
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Necessity of relays for HID's?
Hey,
I've looked around the forum and read a good deal about properly installing HID's. Generally, people have said that relays are unnecessary to operate xenons. The ECU settings simply have to be changed to 'xenon=present'.
But... I had read and heard elsewhere that relays are primarily needed as a protection feature. When HID's first ignite, the bulbs draw more current than stock halogens. The amount of current is enough to cause the power wire to melt over time because the wire is designed to handle only the lower current required by halogens. Is that not the case for the c230k ss? Is the power wire already capable of handling the current required by HID's since HID's are an option for the c230? I'd GREATLY APPRECIATE any help! Thanks!
FYI
Car is 2004 c230k ss.
HID kit consists of (OEM) Philips Generation 3 Ballasts, Philips 4100K D2S bulbs
Thanks again!
-Solus
I've looked around the forum and read a good deal about properly installing HID's. Generally, people have said that relays are unnecessary to operate xenons. The ECU settings simply have to be changed to 'xenon=present'.
But... I had read and heard elsewhere that relays are primarily needed as a protection feature. When HID's first ignite, the bulbs draw more current than stock halogens. The amount of current is enough to cause the power wire to melt over time because the wire is designed to handle only the lower current required by halogens. Is that not the case for the c230k ss? Is the power wire already capable of handling the current required by HID's since HID's are an option for the c230? I'd GREATLY APPRECIATE any help! Thanks!
FYI
Car is 2004 c230k ss.
HID kit consists of (OEM) Philips Generation 3 Ballasts, Philips 4100K D2S bulbs
Thanks again!
-Solus
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From: www.Traben-Trarbach.de
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Startup currents for a lamp load produce a very high short term spike on the system. More so than a motor and/or resistive load. The other factor needing to be taken into account here is how many wires are bundled together, load carried by each one, etc. For example: A 22 AWG in a bundle, protected by 5 amps, can carry more current when its on its own in free air. Even so wire is resisitive it will not heat up instantaneously but will take a finite amount of time. Therefore the initial short term current spike would only be detrimental if the current were high enough to turn that wire into a fusable link. In the case of HID versus halogen you won't find this since halogen need a higher running current than HID for a similar light output: 55W versus 35W. Now if you go to 80W or 100W halogens you would stress the wire because you are increasing the current requirement by 60 % to 80% respectively. HTH
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From: Louisiana
E320
Originally Posted by amdeutsch
Startup currents for a lamp load produce a very high short term spike on the system. More so than a motor and/or resistive load. The other factor needing to be taken into account here is how many wires are bundled together, load carried by each one, etc. For example: A 22 AWG in a bundle, protected by 5 amps, can carry more current when its on its own in free air. Even so wire is resisitive it will not heat up instantaneously but will take a finite amount of time. Therefore the initial short term current spike would only be detrimental if the current were high enough to turn that wire into a fusable link. In the case of HID versus halogen you won't find this since halogen need a higher running current than HID for a similar light output: 55W versus 35W. Now if you go to 80W or 100W halogens you would stress the wire because you are increasing the current requirement by 60 % to 80% respectively. HTH
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Joined: May 2004
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From: Rhode Island
Debadged 6-Speed '05 C320 Sports Coupe
Originally Posted by amdeutsch
Startup currents for a lamp load produce a very high short term spike on the system.
For the vehicle wiring harness, all this has a neglible effect, as it is all internal to the ballast. From the perspective of the wiring harness, the lamp is either on or off, drawing the same nominal current, or not.
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From: www.Traben-Trarbach.de
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Originally Posted by wingless
Actually, a Xenon lamp ballast stores the energy required for ignition on capacitors within the ballast. At turn on, the capacitors dump that stored energy to create a very short duration high voltage, >25KV, ignition pulse. After the lamp ignites and the gas becomes plasma between the electrodes, the ballast regulates the lamp at a constant power. There are short-term startup changes while the plasma temperature changes.
For the vehicle wiring harness, all this has a neglible effect, as it is all internal to the ballast. From the perspective of the wiring harness, the lamp is either on or off, drawing the same nominal current, or not.
For the vehicle wiring harness, all this has a neglible effect, as it is all internal to the ballast. From the perspective of the wiring harness, the lamp is either on or off, drawing the same nominal current, or not.
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Thread Starter
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Joined: Oct 2004
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Hi 
I looked around the forum and the internet for some HID installation FAQ's/instructions and learned some stuff.. but I couldn't find a complete guide. Does anyone have one? Or know anyone that can help with the steps? I saw Young's thread, which was helpful, but the pictures depicting his work are no longer posted.
Again, the kid consists of Generation 3 Philips Ballasts, 4100K D2S Philips bulbs, and wiring harnesses (all OEM I believe...)
Thanks!
SoluS
I looked around the forum and the internet for some HID installation FAQ's/instructions and learned some stuff.. but I couldn't find a complete guide. Does anyone have one? Or know anyone that can help with the steps? I saw Young's thread, which was helpful, but the pictures depicting his work are no longer posted.
Again, the kid consists of Generation 3 Philips Ballasts, 4100K D2S Philips bulbs, and wiring harnesses (all OEM I believe...)
Thanks!
SoluS
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Joined: May 2004
Posts: 911
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From: Rhode Island
Debadged 6-Speed '05 C320 Sports Coupe
Originally Posted by solus
Thanks! Reply was very helpful
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One option is to cough up $100 to an administrator to increase your post count by 100 to decrease the static from each post.
Banned
Joined: May 2004
Posts: 1,194
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From: Australia
Originally Posted by solus
Hey,
I've looked around the forum and read a good deal about properly installing HID's. Generally, people have said that relays are unnecessary to operate xenons. The ECU settings simply have to be changed to 'xenon=present'.
But... I had read and heard elsewhere that relays are primarily needed as a protection feature. When HID's first ignite, the bulbs draw more current than stock halogens. The amount of current is enough to cause the power wire to melt over time because the wire is designed to handle only the lower current required by halogens. Is that not the case for the c230k ss? Is the power wire already capable of handling the current required by HID's since HID's are an option for the c230? I'd GREATLY APPRECIATE any help! Thanks!
FYI
Car is 2004 c230k ss.
HID kit consists of (OEM) Philips Generation 3 Ballasts, Philips 4100K D2S bulbs
Thanks again!
-Solus
I've looked around the forum and read a good deal about properly installing HID's. Generally, people have said that relays are unnecessary to operate xenons. The ECU settings simply have to be changed to 'xenon=present'.
But... I had read and heard elsewhere that relays are primarily needed as a protection feature. When HID's first ignite, the bulbs draw more current than stock halogens. The amount of current is enough to cause the power wire to melt over time because the wire is designed to handle only the lower current required by halogens. Is that not the case for the c230k ss? Is the power wire already capable of handling the current required by HID's since HID's are an option for the c230? I'd GREATLY APPRECIATE any help! Thanks!
FYI
Car is 2004 c230k ss.
HID kit consists of (OEM) Philips Generation 3 Ballasts, Philips 4100K D2S bulbs
Thanks again!
-Solus
Thread Starter
Almost a Member!
Joined: Oct 2004
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I'm assuming that the wiring loom you're talking about is the one that is used with factory installed HID's. That sounds like a possible option, but I'm not sure where I can find one (still learning how to find parts for C230 ). Also, how would you install it?
Thanks,
SoluS
). Also, how would you install it?Thanks,
SoluS
Banned
Joined: May 2004
Posts: 1,194
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From: Australia
Originally Posted by solus
I'm assuming that the wiring loom you're talking about is the one that is used with factory installed HID's. That sounds like a possible option, but I'm not sure where I can find one (still learning how to find parts for C230 ). Also, how would you install it?
Thanks,
SoluS
). Also, how would you install it?Thanks,
SoluS
