I thought I'd go for a benign, non controversial thread title!
If I, as a DIYer, approached you, as an electrician, asking how we could work together to legally interface a home automation system with various existing lights and appliances, what would be your concerns and discussion points? The objective being for the installation to be legal and safe.
The home automation system may provide 12V or 5V outputs suitable for driving relays, and typical interfaces might be relays, solid state relays, and contactors all with screw terminals.
Let's initially consider 3 scenarios.
1. Modify the cabling to an existing light fitting in a non notifiable place (eg. bedroom) to provide control via automation while retaining local control via the wall switch. Possible Approach :- intercept and break out the cable to the light switch in either a JB or a plastic enclosure in an accessible place. Relay installed in the enclosure with the contacts duplicating the action of the wall switch. CAT5 or alarm cable used for the control signal to the relay. Contacts on relay sized appropriately for relevant MCB/RCBO. I am aware that the automation would switch the light on with no way of switching it off again from the local wall switch.
2. Same as 1, however the light fitting (but not the wiring intercept point) is in a kitchen or bathroom.
3. Modification of the 240V cabling from the boiler to the room thermostat to allow control via automation. Possible approach same as 1. ie, relay in a box.
1st question. Would a relay be classed as a switch in 2.c.i of Schedule 4? I used this link. http://www.legislation.gov.uk/uksi/2010/2214/schedule/4/made . Would any of these scenarios be non notifiable?
2nd question, Would you be happy with the approach above or would you suggest a different solution? Assume a retrofit, so not practical (unfortunately) to route all supply and switch cabling to a central point and have a bank of DIN mounted relays.
Other questions probably to follow...
If I, as a DIYer, approached you, as an electrician, asking how we could work together to legally interface a home automation system with various existing lights and appliances, what would be your concerns and discussion points? The objective being for the installation to be legal and safe.
The home automation system may provide 12V or 5V outputs suitable for driving relays, and typical interfaces might be relays, solid state relays, and contactors all with screw terminals.
Let's initially consider 3 scenarios.
1. Modify the cabling to an existing light fitting in a non notifiable place (eg. bedroom) to provide control via automation while retaining local control via the wall switch. Possible Approach :- intercept and break out the cable to the light switch in either a JB or a plastic enclosure in an accessible place. Relay installed in the enclosure with the contacts duplicating the action of the wall switch. CAT5 or alarm cable used for the control signal to the relay. Contacts on relay sized appropriately for relevant MCB/RCBO. I am aware that the automation would switch the light on with no way of switching it off again from the local wall switch.
2. Same as 1, however the light fitting (but not the wiring intercept point) is in a kitchen or bathroom.
3. Modification of the 240V cabling from the boiler to the room thermostat to allow control via automation. Possible approach same as 1. ie, relay in a box.
1st question. Would a relay be classed as a switch in 2.c.i of Schedule 4? I used this link. http://www.legislation.gov.uk/uksi/2010/2214/schedule/4/made . Would any of these scenarios be non notifiable?
2nd question, Would you be happy with the approach above or would you suggest a different solution? Assume a retrofit, so not practical (unfortunately) to route all supply and switch cabling to a central point and have a bank of DIN mounted relays.
Other questions probably to follow...