Meggitt vibro-meter SpeedSys300 ODS301, User Manual

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USER MANUAL Document reference MAODS301/E
SpeedSys300 ODS301 overspeed detection system Edition 4 - May 2022
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Installation considerations
INSTALLATION OF A SPEEDSYS300 ODS301
Accordingly, to obtain a 2oo3 voting logic structure, the safety relays from three SpeedSys300
ODS301 modules should be connected (hardwired) together in combination, as shown in
Figure 3-6 .
Figure 3-7 provides an example of how to hardwire safety relay 1 of three SpeedSys300
ODS301 modules to obtain a 2oo3 voting logic structure.
Because a SpeedSys300 ODS301 module’s safety relays – relay 1 and relay 2 – are
double-pole single-throw (DPST) relays, there are several ways in which three modules can
be hardwired in combination to obtain a 2oo3 voting logic structure.
Table 3-11 illustrates the way in which a 2oo3 voting logic structure can be implemented using
the safety relay 1 of three SpeedSys300 ODS301 modules.
Table 3-11: 2oo3 – using safety relay 1 of SpeedSys300 ODS301 modules
SpeedSys300 ODS301 modules
2oo3 to customer
#1 #2 #3
B17 ↔ B20
B17 ↔ B20
B20 ↔ B17
B18 ↔ B18 ↔ B18 ↔ 2oo3 connection to customer circuit
B19 ↔ B19 ↔ B19 ↔ 2oo3 connection to customer circuit
Figure 3-7: 2oo3 – example using safety relay 1 of SpeedSys300 ODS301 modules