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50 HZ fluorescent ballast

Posted By: jkraft

50 HZ fluorescent ballast - 05/25/13 05:15 AM

I'm looking for a replacement ballast for a 65W fluorescent lamp off of an Italian woodworking machine, 220V 50 Hz.
I think it's a Phillips lamp #TLM 65W/33 RS.
Any suggestions?
Can I use a 60Hz ballast?
Posted By: gfretwell

Re: 50 HZ fluorescent ballast - 05/25/13 07:51 AM

What voltage are you going to be running this on?

I think if you match the ballast to the voltage you should be OK.
Posted By: Texas_Ranger

Re: 50 HZ fluorescent ballast - 05/25/13 01:02 PM

It's probably a plain choke with a starter, at European voltages they work well and are cheap. What happened to the old ballast? Usually these are almost indestructible. Or is it an electronic one?
Posted By: jkraft

Re: 50 HZ fluorescent ballast - 05/26/13 05:07 AM

The fixture runs at the machine voltage 220V 50Hz.
The existing ballast shorted/burned and consisted of three components; a small transformer/starter/and ???. It's an explosion proof assembly and all fits into a 3" diameter by 16" long cast aluminum tube.
I was hoping I could find an electronic unit to just drop in there.
Posted By: gfretwell

Re: 50 HZ fluorescent ballast - 05/26/13 07:58 AM

I bet something like this would work.
Posted By: Scott35

Re: 50 HZ fluorescent ballast - 05/26/13 05:57 PM


A High Frequency Electronic Fluorescent Ballast will work as a replacement for the original (Barbecued) Discrete Component Reactor Assembly.

Nearly all High Frequency Electronic Ballasts are rated for 100 to 277 VAC Line Input, at 50-60Hz.

These Ballasts "Do Not Care" about the Line Input Frequency, because the first section of the Ballast is the Rectifier Input, which converts the Input AC into a "Usable" DC supply.
The DC is then Inverted to a "Choked" Output AC, at > 40kHz, to drive the Fluorescent Lamp.

You may choose to drive the Lamp with Hot Cathode Operation (Rapid Start & Programmed Start Ballasts), or with Cold Cathode Operation (Instant Start Ballasts).
In either case, the original Discrete Component Ballast Kit will not be needed for Operation, and may be tossed into your favorite Recycle Materials Container.

Re: Operating a 60 Hz Rated Electromagnetic / Linear Reactor Ballast on a 50 Hz System...

Operating the Ballast at < / > 95% rated Hz will cause Heat Issues, and lead to premature Winding failure, due to "Hot Spot" Concentrations on the Windings / Core Laminations.
If you decide to install an Electromagnetic (Linear Reactor) Ballast, be sure to match the Voltage and Frequency available at your location.

Re: The Original Discrete Component Ballast Kit..
[ --- Read: The Ballast Kit which leaked all its Smoke out...;) --- ]

*** PRE-NOTE ***

I thought it would be interesting to elaborate on the operation of the Lamp / Ballast Assembly.
Feel free to read through, or skip over the following Techno-Jargon.



The existing ballast shorted/burned and consisted of three components; a small transformer/starter/and ???.

These Components should be:

1: The "Small Transformer" = The "Actual Ballast"; The Discrete Component which "Chokes" (limits) the Current flowing through the Lamp.

This Component is a "Linear Reactor"; a simple coil of enameled Wire, wound on a Laminated Core which has a large "Gap" to Permeate.
The Coil is wound so the direction of Current Flow is opposed by the Direction of Magnetic Flow.

The results are; as the Current Flow increases, the opposing Magnetic Flux increases, and thus limits the total Current which may flow through the Reactor (i.e.: Inductor Principle)


2: The "Starter" = The Lamp's "Temporary Cathode Heater Device";

The Starter enables Line Input AC (limited via the Ballast, and the Fixed Resistance of the Cathodes) to Temporarily flow through the Lamp's Cathodes (Filaments at each end of the Fluorescent Lamp assembly), in order to Heat the Cathodes.
With Hot Cathodes, the Emission of Electrons / Majority Charge Carriers is greatly enhanced during initial Cold Starting.

With the Cathodes Heated at Cold Start, the Charge Carriers may cross the Lamp under a low Pressure - in the order of 100 to 200 Volts.

Once the Lamp has an initiating Arc setup between the ends, every thing changes, and the Lamp now becomes a Path of "Negative Resistance" due to the internally confined Plasma.
That is why these Lamps require a Ballast to limit the Current.

Starting the Lamps may also be done in a "Cold Cathode" fashion, which does not require the Cathodes to be Heated at Start, or throughout the Operation, in a method known as "Instant Start".

An Instant Start Ballast develops a High Pressure (Voltage) between the Two Lamp Lead connections to the separate Cathodes - in a technique similar to a "Tank Circuit" used for Camera Flash Lamps.

The High Pressure developed between the Lamp Leads / Lamp Ends, kind of "Forces" Majority Charge Carriers out of the Cathodes and across the Lamp, towards the "Side" with lower or higher Potential.
Starting Voltages in the range of 600 - 700VAC are common for Instant Start.

As with the Hot Cathode Starting, once an initiating Arc has been established across the Lamp, a Plasma is setup and the Lamp becomes operational.
The Ballast now performs its primary task: regulation of Current.

FYI; When the Lamp is Operating, the Voltage across the Lamp drops significantly.
If a 430 ma (Milli-Amp) Lamp is operating, and drawing 32 Watts from the AC Power Supply, the Operating Voltage across the Lamp will be 74.4 VAC.

Same goes for the "HO" and "VHO" type Lamps.
If an 800 ma "HO" Lamp is operating, and drawing 60 Watts from the AC Power Supply, the Operating Voltage across the Lamp will be 75 VAC.


3: The "???" = Most Likely "Power Factor Correction / Lamp Regulation Capacitor;

If this Luminaire is a Two Lamp Fluorescent, it is almost certainly a Capacitor!

Two-Lamp Operation via "Preheat Start" will be aided by having One Lamp's Current drawn through a Capacitor.

If there is only One Lamp, the Capacitor would be for Correcting the Power Factor of the Lamp, as the Lamp will store much less Reactive Power than the Reactor Coil.

I will end here, as my Wife is trying to get me away from the Computer.....

--Scott (EE)
Posted By: Texas_Ranger

Re: 50 HZ fluorescent ballast - 05/26/13 10:38 PM

Here's an interesting description:

The last sentence explains the classic cycling of fluorescents with traditional ballasts and starters. I actually know a fixture in which this cycling mechanically rattles the glass shade. Incredibly scary sound in an empty tiled room!
Posted By: jkraft

Re: 50 HZ fluorescent ballast - 05/28/13 01:44 AM

Thanks Scott, I appreciate the explanation.
So I will look to get an electronic ballast rated for a 6' 72W lamp and try that.
Posted By: Scott35

Re: 50 HZ fluorescent ballast - 05/30/13 07:27 AM


Good luck, and let us know if you experience any difficulty obtaining the correct Ballast.

--Scott (EE)
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