Tempco TEC-2500, Инструкция по эксплуатации

Страница: 77 / 108

73
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:
Unlike a conventional SSR, the VPFW SSR always gives the output an even number of half cycles (full wave) as shown
in the following diagram.
The VPFW switches the load without DC current, minimizing the harmonic current and stress on the load. This prolongs
the load life.
Since the duty cycle (i.e., output power level) of the control input is small, the off-period will be extended to keep the
output resolution such that the conversion error is minimized. As low as 0.1% timing error can be achieved. Hence,
VPFW SSR is particularly suitable for smoother control.
NOTES:
1. The VPFW SSR can be used to drive a resistive load and some types of inductive loads such as relay, contactor,
magnetic switch, solenoid valve, etc. However, it can not drive motor or capacitive loads .
2. Only AC power can supply a VPFW SSR, otherwise it will not operate properly.