Yaskawa 120 Series I/O Modules - Manual (Page 265)

6 Installation and Wiring
6.4.2 AC Output Modules
6-38
5) Minimum Switching Voltage/Current
A triac is used for the output switch of AC output Modules. Since a triac cannot
operate stably if the load is less than the specified minimum switching voltage/cur-
rent, be sure to use a load with a rated current level higher than the minimum
switching voltage/current.
If the minimum switching voltage/current cannot be maintained, connect a dummy
resistor in parallel with the load so that the total switching voltage/current is higher
than the minimum switching voltage/current.
Fig. 6.17 Minimum Switching Voltage/Current
6) Leakage Current from Output Modules
Leakage current flows from an AC Output Module when the Module is OFF, and a
light load, such as a relay, connected to the AC Module may turn OFF because of
the leakage current.
The following diagram shows a load device with the load impedance is 6 k Ω con-
nected to an AC Output Module. This load will not turn OFF due to the leakage cur-
rent of 3 mA.
Fig. 6.18 Leakage Current from Output Modules
Dummy resistor
Light load
Load
100 VAC
(200 VAC)
Output
Output
Common
1-1
Common
1-2
AC Output Module
Output
Load device
Leakage current = 3 mA
Load impedance
ZL
Common
Load power supply
(100/200 VAC)