5 2 Variable Period Full Wave SSR ( VPFW SSR )
5 2 Variable Period Full Wave SSR ( VPFW SSR )
VPFW SSR is a variable period full wave solid-state relay. It can provide a zero
cross output with superior controllability compared to a conventional SSR with
a fixed time base. The block diagram of VPFW SSR is shown as follows:
VPFW SSR is a variable period full wave solid-state relay. It can provide a zero
cross output with superior controllability compared to a conventional SSR with
a fixed time base. The block diagram of VPFW SSR is shown as follows:
+
AC
Input
AC
Input
AC
Output
AC
Output
Pulsed Voltage
Control Input
Pulsed Voltage
Control Input
Unlike a conventional SSR, the VPFW SSR always give the output an even number of
half cycles ( full wave ) as shown in the following diagram.
Unlike a conventional SSR, the VPFW SSR always give the output an even number of
half cycles ( full wave ) as shown in the following diagram.
Figure 5.2
Block Diagram of VPFW SSR
Figure 5.2
Block Diagram of VPFW SSR
Power Input
Power Input
Control Input
Control Input
Power Output
Power Output
VPFW SSR
VPFW SSR
Conventional SSR
Conventional SSR
The VPFW switches the load without DC current, hence minimize the harmonic
current and stress on the load. The load life is prolonged.
The VPFW switches the load without DC current, hence minimize the harmonic
current and stress on the load. The load life is prolonged.
As the duty cycle ( ie. output power level ) of the control input is small, the off
period will be extended to keep the output resolution so that the conversion
error is minimized. As low as 0.1% of timing error can be achieved. Hence,
VPFW SSR is particularly suitable for a smoother control.
As the duty cycle ( ie. output power level ) of the control input is small, the off
period will be extended to keep the output resolution so that the conversion
error is minimized. As low as 0.1% of timing error can be achieved. Hence,
VPFW SSR is particularly suitable for a smoother control.
Figure 5.3 VPFW SSR
vs. Conventional SSR
Figure 5.3 VPFW SSR
vs. Conventional SSR
NOTES:
1.The VPFW SSR can be used to drive
resistant load and some types of
inductance load such as relay,
contactor, magnetic switch, solenoid
valve etc. However, it
2. Only
can supply VPFW
SSR, otherwise, it will not operate
properly.
can not drive
Motor and Capacitance Load.
AC power
1.The VPFW SSR can be used to drive
resistant load and some types of
inductance load such as relay,
contactor, magnetic switch, solenoid
valve etc. However, it
2. Only
can supply VPFW
SSR, otherwise, it will not operate
properly.
can not drive
Motor and Capacitance Load.
AC power
UM25001C
84
