Selenium Rectifier Stacks
An example of a selenium rectifier stack number is shown at the bottom of the chart. Decoded, this number means that the stack has the following characteristics: The assembly is forced-air cooled (F prefix), the cells are 5 by 6 inches (code S), they have a 33 volt rating, they are Hi-Density type, they are circuited as a single-phase bridge (code B), and two of them are used in series in the assembly. The assembly has a Multi-Coat - 24 hour salt spray
finish (code T), a stud mounting with brackets (code B), and three cells are used in parallel on each arm of the bridge.
To aid in ordering selenium rectifiers this section presents ordering instructions, followed by the Selenium Rectifier Stack Assembly Numbers chart and the Superior Hi-Density Vacuum Process Selenium Rectifier Cells listing, which provides information on the selenium cells themselves.
Selenium rectifier stacks are made up of selenium cell's which are mounted together and circuited as required for each application. They are available in configurations to suit all of the rectifier circuits shown in the Rectifier Design Diagrams in section 1.
Superior Induction is a leader in supplying selenium rectifier stacks. In fact, the company can assemble and deliver any selenium rectifier in 48 hours or less. And the stacks contain extremely high-quality, high-density, vacuum-process cells to ensure uniformity, stability, and long life.
To accommodate selenium rectifier customers, Superior Induction accepts quantity orders at the quantity price and delivers the needed rectifiers on a rush basis, while the balance of the order is shipped by low-cost carrier.
The variables involved in assembling selenium rectifier stacks are similar to those discussed earlier concerning silicon rectifier stacks. And to keep the information manageable, Superior Induction uses assembly numbers that are similar to the ones described in the silicon rectifier stack section. These numbers are stamped on the selenium rectifier stacks themselves and the Selenium Rectifier Stack Assembly Numbers chart in this section can be used for decoding them and also as a guide for selecting selenium rectifier stacks.
Superior Induction selenium rectifier stack assembly numbers consist of eight sections, each of which uses letters or numbers to describe a characteristic of the stack. Prefixes are also used as noted above the chart to show forced air cooling and wide spacing of cells.
SELENIUM RECTIFIER ORDERING INSTRUCTIONS
The following outlines the information you need when you call to order selenium rectifiers. (If you are unable to find some of this information, call and we will be glad to assist you.)
1. Measure the diameter of the plates (or cells) if they are round or measure the height and width if they are square or rectangular.
2. Measure the B dimension (the length of the rectifier as illustrated in the accompanying diagram). Also, if the rectifier has brackets, measure the P and E dimensions.
3. Count the number of plates in the rectifier.
4. Observe the orientation of the terminals-all on one side? On opposite sides?
5. If possible, determine the voltage input, number of phases, and the direct current volts and amps for the rectifier.
TYPICAL SELENIUM RECTIFIER STACKS