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Gold concentration determination

I work on a medical device facility in which gold plating is performed. Gold solution is dispensed manually into the bath where plating is performed. In order to know when to refill the bath, gold thickness is determined on already coated plates, when coat thickness is closed to lower specification limit, fresh gold solution is manually dispensed to the bath. Is there any automatic method, (for example, an electrode) in which I can monitor directly into the bath the gold concentration, so I can automatize the gold refilling process?

JULIO MARTINEZ
- DOMINICAN REPUBLIC
2006

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Hello, Julio. Although I am answering a slightly different question than you asked, a basic instrument that you are apparently not yet applying is an "Amp-hour meter" (some would call it an amp-minute meter). The amount of gold consumed is directly proportional to the ampere-hours of current applied (according to Faraday's Law of Electrolysis), and it is common practice to attach a totalizer across the rectifier shunt so that you can track the gold as it is consumed. Any of the manufacturers of rectifiers can offer this as a free-standing unit, and they're not terribly expensive.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Just to add on, some ampere-Hour meter is outfitted with volumetric pump and a solution replenisher reservoir. At a pre-set amp-hour, it pumps out, the required amount of replenisher to the plate solution.

Hamilton Solidum
- Mays Landing, New Jersey
2006