Volvo 819 E - Page 7

Group 28 Ignition systems
Design and function - Overview
Review of electronic ignition systems - I
TSZ : An electronic ignition system in which the function performed by contact breaker points in conventional sys-
tems is carried out by an induc tive pulse generator. (Roughly translated, the abbreviation TSZ - which stands for
Transistor Spolen lundung - means 'Transistorized coil ignition'.) The pulse generator signals are transmitted to a
'co ntrol unit' which regulates the coil charging period. The system also inco rporate s a cent rifugal generator and a
baltast resistor. Designated TSl-4, the variant for 6-cylinder engines (B28A1EiF) was used on 700 series cars from
1982 to 1986.
TZ ·28H: As the designat i on indicates , this is a trans i stor ized system employ i ng a Hall generator to supply the si gnals
used by the ' control unit' to c ontrol the pr i mary current in the ign i tion coil. A vacuum advance un it on the distributor
varies the timing with engine load . Although t he sys tem was used on some 700 series models produced in 1984, it
was almost completely superseded by other systems in 1985 as the new family of engines entered production . (Un-
like other systems discussed in this con text , TZ-28H is not fully electronic; indeed. it is usually regarded as one of the
group of transistorized systems .)
RfNIX-F: The name is a trademark of the Bendix company . In this system , the contro l unit. power stage and ignition
coil comprise a single un it. Since '985 , Renix-F has been used on 7405 equ i pped with the B 200 K engine and Salex
c.rburettor.
• The letters used in the deS i gnations 01 the var i ous systems are u sually derived from the maker 's nat ive l anguage . wh i le the fig -
ures usually denote the ver Si on and/or var i ant design ation .
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