TOPIC:

I picked up a British book on motorcycle electronics. They use a term I am not familiar with... thyristor - for instance, these are inside a voltage regulator and you can perform tests on the voltage regulator which tests these "thyristors". What is the word we would use here in the States for a thyristor? I think I know but my electrical knowledge is just good enough to get me into trouble bwhahaha

I thought a thyristor was a rectifier?

WG:

en.wikipedia.org/wiki/Thyristor


yup...it's a rectifier

That is what I thought as there ain't much more to an old school voltage regulator. The Brit book I got from Whitehorse Press is by Haynes and is MOST EXCELLENT except for the odd term that isn't the same as what we use. It gives actual tests for a voltage regulator while the thing is off a bike so you don't have to mount it to find it is putting out 73 Volts DC hehe A lot of the specific tests are for older Kaws using 3 phase alternators (stators as found on most of our bikes)! Good stuff. Thanks! I didn't want to have to call Saunders again as his Brit is starting to fade and he isn't all that useful for translating hehe

WG: What book is this? Where and how did you get it?

no,no its one of those fancy new exercise machines works the thys and rists at the same time,i think griz bought one which im sure he will be happy to post! what?

Thyristor is a general name for any of several devices in a family of semiconductor devices made from 4 layers of Silicon. (Transistors have 3 layers and diodes have 2.)

The thyristor used in regulators (for permanent magnet alternators only) are SCR's (silicon controlled rectifiers). The SCR is not used as a rectifier even though it can. It has a more specialized application. Common diodes are what are used in rectifiers.

The SCR is the main device, but certainly not the only device, in a regulator. (Actually, 3 phase uses 3 SCR's and single phase uses 2 SCR's, typically).

Often, a diagram may only show the SCR to represent a regulator, but, in fact, there are more components implemented that are not shown.

By the way, the British are not known for their electrical engineering expertise in automotive applications.

Michael - the book is a Haynes pub... it is in the shop right now... found my first error in the book yesterday bwhahahaha

They test a Kaw volage regulator (not on a running bike) using a multimetern in Ohms scale. They put probes on black and brown wires out of the voltage regulator and get 1050 Ohms in one direction and 300 in the other. I tested BOTH voltage regulators on my carb test bikes where they have been service for years and work fine in a running test (under 15VDC at 4K rpm) and both showed 1050 OHMS IN BOTH DIRECTIONS!

Anyway, the Haynes book called "Motorcycle Electonics Techbook" has lots of Kaw related stuff. I bought it from:
Whitehorse Gear
customer service 603 356 6556
catalog requests 603 356 6633
email: This email address is being protected from spambots. You need JavaScript enabled to view it.
internet www.whitehorsegear.com

very good loudhvx you are right on the money . the KZ's have 3 phase full wave permenant magnet systems. featuring a delta wound stator.full wave rectification and a regulator that gates excessive current to ground I like to add that the term of dynamo is used as the stator but I understand the dynamo to be both the stator and rotor as a team.. dynomite!!

loudhvx wrote:

Thyristor is a general name for any of several devices in a family of semiconductor devices made from 4 layers of Silicon. (Transistors have 3 layers and diodes have 2.)

The thyristors name is homage to the thyratron .

Thyratron + Transistor = Thyristor

thyra, greek for door
tron, as in electron

thyratron = door for electrons

little doubt the term 'gate', given to the controlling terminal on field effect transistors, was a thematic choice.

Post edited by: Duck, at: 2006/06/29 10:45