Caliper2PC
Using Caliper2PC DRO to turn on my lathe's engine - Printable Version

+- Caliper2PC (https://www.caliper2pc.de/forum)
+-- Forum: English (https://www.caliper2pc.de/forum/forumdisplay.php?fid=4)
+--- Forum: Hardware (https://www.caliper2pc.de/forum/forumdisplay.php?fid=5)
+--- Thread: Using Caliper2PC DRO to turn on my lathe's engine (/showthread.php?tid=12)



Using Caliper2PC DRO to turn on my lathe's engine - Lorenzo - 03-16-2019

   
I realized the Caliper2PC interface has output ports and would like to use some of them to turn my machines' engines on and off. I though about using relais for the power side.

Any advice?


RE: Using Caliper2PC DRO to turn on my lathe's engine - Ben - 03-17-2019

The output ports of the Caliper2PC interface have 5V levels (0V = low, 5V = high). A relais with optocoupler that works on 5V can be used to switch your motors.

These relais cards can be found on eBay or on Aliexpress see attachment.


RE: Using Caliper2PC DRO to turn on my lathe's engine - Tomer - 03-20-2019

The Caliper2PC's output ports can drive a current of 25 mA. This is more than enough to drive optocouplers that switch powerful relais.

Please note that connecting devices to the grid with high voltage is a dangerous task and should be performed by certified electricians only  Exclamation


RE: Using Caliper2PC DRO to turn on my lathe's engine - Lorenzo - 03-20-2019

Why are there 3 connectors GND, IN and Vcc on the relais card? Huh


RE: Using Caliper2PC DRO to turn on my lathe's engine - Ben - 03-24-2019

(03-20-2019, 10:36 AM)Lorenzo Wrote: Why are there 3 connectors GND, IN and Vcc on the relais card? Huh

The relais PCBs with optocoupler use the optocoupler as a switch. The Caliper2PC I/O output port handles a maximum of 25 mA. That is enough to drive the optocoupler's LED but it is not enough current for the relais' coil. Therefore the Vcc is needed. It can provide the current needed by the relais' coil. With most relais PCBs an external power supply can be used to drive the coil. Connecting the relais card to the Caliper2PC interface just use this pin assignment:

Relais Card    -     Caliper2PC interface (RJ45 Patch cable)

GND   =    GND            (orange / white)
IN       =    IO - Output (green / white)
Vcc     =   5V                (brown)