Wavetronix Click 500 (programmable controller) (CLK-500) - User Guide - Manual (Page 50)

CHAPTER 6 • CLICK 500 49
current transformers have a unique hinge and locking snap that allows attachment without
interrupting the current-carrying wire. Snap the transformer around either the AC line
wire or AC neutral wire, but not both. Make sure that the locking snap is secure by pressing
down firmly when making a connection (see Figure 6.10).
Figure 6.10 – Transformers
Caution
Do not connect 110 VAC or higher directly to a digital input when it is configured to
monitor low-level AC. Always use an AC current transformer to reduce the magnitude
of the AC voltage.
The intended application for the AC input transformers is to measure which of the signal
indications (red, yellow, green) on a standard incandescent or LED signal light is illumi-
nated. These inputs can be used with any type of standard traffic cabinet to determine which
indications are on or off. When enough current is being supplied by the traffic cabinet load
switches to activate a 1 W load, the digital input will signal that AC is on (otherwise, the
input will signal that the AC is off). This high-level of sensitivity allows the input to work
with low power LED signal lights that draw only 5 W.
When used to monitor low-level AC, the digital inputs can also be used in any other indus-
trial application where it is necessary to determine if an AC load is powered on or off. For
example, an alarm could be generated if a device, which is supposed to run continuously,
turns off.
Contact Closure Digital Input
If a digital input is used to monitor contact closures, connect the I1+ pin to one side of the
contact output and the I1- pin to the other side of the contact output. For demonstration
and troubleshooting purposes you can use the digital inputs to monitor the contact closure
outputs of the Click 500 itself. To do so, wire I1+ to O1+, I1- to O1-, I2+ to O2+ and I2- to
O2-.