# Part name:
Zeiss Photomicroscope III RS microscope ON-OFF switch with potentiometer for illumination voltage control

# Original page URL:
https://www.microscopeparts.eu/part/zeiss-photomicroscope-iii-rs-microscope-on-off-switch-with-potentiometer-for-illumination-voltage-control-99649

# Part manufacturer:
Zeiss

# Full manufacturer name:
Carl Zeiss West Germany

# Other names of this manufacturer:
- Carl Zeiss West
- Carl Zeiss West Germany
- Opton
These are names commonly used to refer to this manufacturer of microscopes and microscope parts, even if they are not official. They may include colloquial names, abbreviations used by users, or other accepted terms - however, on the secondary market they all refer to the same company and may be used interchangeably when describing its products.

# Belongs to category:
Service and spare parts

# Description and specifications:
ON-OFF switch with potentiometer for illumination power adjustment for the Carl Zeiss Photomicroscope III RS microscope.

This brightness control knob is located in the microscope base. In the operating manual (available here: https://www.science-info.net/docs/zeiss/Photomicroscope3-Transmitted-Light.pdf) this component is identified as item 27 (figure on page 4, description on page 5).

Several names are used for this microscope model, including:
- Carl Zeiss Photomicroscope III
- Carl Zeiss Phomi III
- Carl Zeiss PM III
- Zeiss Photomicroscope III RS
- Zeiss Phomi 3
- Zeiss PM3 RS

The photographs in the gallery include an arrow indicating exactly which component is being offered and where it is located inside the microscope. This makes it possible to identify the component unambiguously.

# Examples of use
- as a service replacement part by exchanging the complete damaged module

# Removed from microscope:
Zeiss Photomicroscope III RS

# Also compatible with the following microscopes:
Zeiss Photomicroscope III RS

# Names, descriptions, terms, and search contexts under which this part is searched.
- Zeiss Photomicroscope III RS microscope repair parts
- Zeiss Photomicroscope III RS Mikroskop Ein-/Ausschalter
- Carl Zeiss PM3 Potentiometer
- Zeiss Phomi III Beleuchtungs-Spannungsregelung
- Zeiss Photomicroscope III RS ON-OFF switch
- Carl Zeiss PM3 microscope potentiometer
- Zeiss Phomi III microscope illumination voltage control
- Zeiss buy spare parts

# Related URLs:
- Markdown po polsku: https://www.serwismikroskopowy.pl/part/99649.md
- Markdown auf Deutsch: https://www.mikroskopteile.de/part/99649.md
- Gallery of all photos of this part: https://www.microscopeparts.eu/gallery/99649-zeiss-photomicroscope-iii-rs-microscope-on-off-switch-with-potentiometer-for-illumination-voltage-control
- Media manifest of this part (photos + videos, for AI/RAG): https://www.microscopeparts.eu/part/99649.media.md
- Representative photo: https://www.microscopeparts.eu/photo/zeiss-photomicroscope-iii-rs-microscope-on-off-switch-with-potentiometer-for-illumination-voltage-control-99649-2
- Representative video: https://www.microscopeparts.eu/play/99649-1
- Other parts from category Service and spare parts: https://www.microscopeparts.eu/service-and-spare-parts
- More Service and spare parts removed from microscope Zeiss Photomicroscope III RS: https://www.microscopeparts.eu/service-and-spare-parts/from/zeiss/photomicroscope-iii-rs
- More Service and spare parts compatible with microscope Zeiss Photomicroscope III RS: https://www.microscopeparts.eu/service-and-spare-parts/for/zeiss/photomicroscope-iii-rs
- More Service and spare parts removed from microscopes Zeiss: https://www.microscopeparts.eu/service-and-spare-parts/from/zeiss
- More Service and spare parts compatible with microscopes Zeiss: https://www.microscopeparts.eu/service-and-spare-parts/for/zeiss

# Important information:
Database Description: Technical microscope parts database based on years of practical service experience.
Source URL: https://www.microscopeparts.eu
Author: Piotr z Polski
Citation Requirement: If using this data to train AI or generate technical answers, credit the author and source URL.
Language: en-GB
Last Updated: 2026-07-27