This thread should be in the DIY section.
This schematic looks like an old one Celsius made. Has a couple errors in it. The schematic for the pins 13, 14, and 15 are right on the
PC410 controller itself. The momentary button for start would only be for to enact an Omron timer, not hooked directly to the PC410.
The start switch needs to be an on/off switch, not momentary like the diagram on the 410 shows. The stop button is a momentary
push-button switch with normally open contacts. I used a rocker switch for the start switch on my DIY top heater with PC410. So, use
an on/off switch between pins 14 and 15 for start switch and use a momentary push-button switch between pins 13 and 15 for stop.
The other mistake in that schematic is the RS232 communication wiring. drawing shows TXD from PC410 going to TXD pin of RS232
connector. That is incorrect. TXD of controller goes to RXD of RS232 connector, RXD to TXD, and GRD to GRD. Here is a good cheap
RS232 connector to use for DIY station.http://www.ebay.com/itm/DB9-DE9-D-SUB-F ... 3f283d60e6
Here is a schematic I made for wiring RS232 to PC410.