On 6/28/2016 5:20 PM,
alan00463@... [Homebrew_PCBs] wrote:
>
> I'm making my first PCB for a thermostat for
> an electric heater. I need to connect the
> electronics to several outside components:
>
> - a thermistor that goes in the oven
> - an thermal fuse to shut off power if it gets too hot
> - battery power & ground
> - 3-conductor connector to an external solid-state relay
>
> I plan to use pin headers and matching sockets for each of
> these four connections. For each of these four connections,
> what criteria should I use to determine whether to put the
> pin header on the PCB and the matching socket on the connect-
> ing cable, or vice versa ?
>
> The thermostat itself and the SSR will fit into a plastic box that
> also contains the battery. So my question pertains to orient-
> ing the headers/sockets inside the plastic box. None of
> the connections will ever be disconnected without first removing
> four retaining screws from the lid of the plastic box.
>
>
Hello, Alan--
Standard procedure is to put sockets on any group of wires that carry
hazardous voltages
and thus could deliver a shock to an unwary person if the connector's
pins were exposed.
Also, when unplugged, exposed pins carrying voltage will inevitably
short-circuit themselves on any
nearby metal (that's one of Murphy's Laws)<g>.
Also, if you're using identical connectors, if possible you should
provide a means of keying
or otherwise identifying which plug mates with which socket. If the
connectors you're
using don't have provisions for keying, label the plugs and sockets.
HTH, and 73--
Brad AA1IP