Simple load shedding solution with Sonoffs - idea.

Kosmik

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Joined
Sep 21, 2007
Messages
20,379
Hi all,

Just want to run this by folks before I go ahead with the basic investment. We are lucky in that we get load shed minimally on our grid unless stage 3 or higher ( on the industrial grid ) but I still want to protect my devices if that escalates. Currently, I want to protect the following circuits, all are plug points and I'm thinking of wiring the switches inline with the respective power cords:

1. 18K BTU Inverter aircon - I'm worried about the ampage here so was thinking of a POW R2 , will let me monitor consumptions as well.
2. Deep freezer - Not sure if can go with a basic due to amapage ( 10A ). Would I have to go higher to a POW R2 here as well?
3. Multiplug running Normal fridge, Kitchen plugs and whatever local appliance the wife plugs in. Most I'm sure draw less than 10A but worried about the fridge.
4. Multiplug running 4KLED TV, 2.1 Sound, Decoder, small game station - Sure I can wire just a Basic here
5. Multiplug running gaming machine with 650W PSU, HP Microserver, 2 x External hardrives, 1 x loadbalancer, 2 x LTE routers and a 1 x AP. Also doubt this will draw 10A so a basic inline as well?

PC's I have hooked to TeamViewer so can do remote shutdown or enable a schedule if needed. For the balance, I just want to ensure a buffer between the load shedding on and off and the devices, so turn off power 5 mins before and restore power 10 mins after.

Basically I'm looking at double the price for the POW units to handle 15A vs the Basics to handle 10A. This would be a temporary solution as I would want to do the house properly at the db level later but would solve a lot of concerns for now. Thoughts? Suggestions?
 

chrisc

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Joined
Aug 14, 2008
Messages
7,927
Will this be automated or will you do it manually?

The OFF cycle is no problem at all. Its the ON which often causes trouble

With the multiple switching taking place, DBs in sub stations and taking strain

A solution I made for several friends is an elapsed time timer. When the power comes back, the timer starts counting down and will restore the power to the circuit after 5 mins

The timer only has 5 amp contacts, so I had this switch a relay which has 2 x 20 amp contacts
 

ghostim

Expert Member
Joined
Dec 27, 2004
Messages
1,640
Ok
My fridge and box freezer is on Clearline refrigeration surge protectors which delays switching on the appliances by 5 minutes.
Next I plan to put the Openhab Pi + the LTE router + AP on UPS.
Then put Sonoff minis before all the tv's, pc's etc.
Write a API integration to Eskom Loadshedding notifications to automate shutting down/poweroff all sensitive equipment 5 min before loadshedding start.
My only headache is the geyser. I can't find anything local that integrate with hassio/openhab
 

BetaProject

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Sep 14, 2015
Messages
127

Kosmik

Honorary Master
Joined
Sep 21, 2007
Messages
20,379
Will this be automated or will you do it manually?

The OFF cycle is no problem at all. Its the ON which often causes trouble

With the multiple switching taking place, DBs in sub stations and taking strain

A solution I made for several friends is an elapsed time timer. When the power comes back, the timer starts counting down and will restore the power to the circuit after 5 mins

The timer only has 5 amp contacts, so I had this switch a relay which has 2 x 20 amp contacts
I was going to automate through the sonoffs scheduler. Basically the sonoff should trigger the appliances to off at the schedule prior to power loss. The on function will be that the sonoffs only switch the appliances back on once loadshedding has passed ( around 5 or 10 minutes after ). Once power is restored, the sonoffs which should remain in a OFF state, communicate back and await the ON activation signal.

Hmmm my only concern is that the routers would need to be up but I can work around that by putting the one sonoff directly on the one routers wifi that has a battery which lasts the whole loadshedding. Then it will receive the on activation and ensure that the wifi network goes up for all the others. Or i just put all the sonoffs directly on that router too. I run a dual router setup with AP and load balancer. Other option is put those systems on a small UPS. They have minimal power draw.

My concern is more around the current draw of the various appliances.
 

PsyWulf

Executive Member
Joined
Nov 22, 2006
Messages
8,738
I've got a Cron timed job on a raspberry Pi that sends a wakeup to devices (PCs/arduino/sonoff) 10minutes after power is up
 

spiff

Executive Member
Joined
Oct 17, 2007
Messages
5,066
Ok
My fridge and box freezer is on Clearline refrigeration surge protectors which delays switching on the appliances by 5 minutes.
Next I plan to put the Openhab Pi + the LTE router + AP on UPS.
Then put Sonoff minis before all the tv's, pc's etc.
Write a API integration to Eskom Loadshedding notifications to automate shutting down/poweroff all sensitive equipment 5 min before loadshedding start.
My only headache is the geyser. I can't find anything local that integrate with hassio/openhab
Care to share device info?
 

ghostim

Expert Member
Joined
Dec 27, 2004
Messages
1,640
Clearline refrigeration surge protectors which delays switching on the appliances by 5 minutes.
 

Dairyfarmer

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Apr 17, 2016
Messages
3,684
My only headache is the geyser. I can't find anything local that integrate with hassio/openhab
Sonoff POW2 flashed with Tasmota.

Get someone to add one to their Banggood order. Much cheaper than local. R155 vs R285
 

Thor

Honorary Master
Joined
Jun 5, 2014
Messages
39,319
Hi all,

Just want to run this by folks before I go ahead with the basic investment. We are lucky in that we get load shed minimally on our grid unless stage 3 or higher ( on the industrial grid ) but I still want to protect my devices if that escalates. Currently, I want to protect the following circuits, all are plug points and I'm thinking of wiring the switches inline with the respective power cords:

1. 18K BTU Inverter aircon - I'm worried about the ampage here so was thinking of a POW R2 , will let me monitor consumptions as well.
2. Deep freezer - Not sure if can go with a basic due to amapage ( 10A ). Would I have to go higher to a POW R2 here as well?
3. Multiplug running Normal fridge, Kitchen plugs and whatever local appliance the wife plugs in. Most I'm sure draw less than 10A but worried about the fridge.
4. Multiplug running 4KLED TV, 2.1 Sound, Decoder, small game station - Sure I can wire just a Basic here
5. Multiplug running gaming machine with 650W PSU, HP Microserver, 2 x External hardrives, 1 x loadbalancer, 2 x LTE routers and a 1 x AP. Also doubt this will draw 10A so a basic inline as well?

PC's I have hooked to TeamViewer so can do remote shutdown or enable a schedule if needed. For the balance, I just want to ensure a buffer between the load shedding on and off and the devices, so turn off power 5 mins before and restore power 10 mins after.

Basically I'm looking at double the price for the POW units to handle 15A vs the Basics to handle 10A. This would be a temporary solution as I would want to do the house properly at the db level later but would solve a lot of concerns for now. Thoughts? Suggestions?
If you want to do a bulk order I did one last year with a couple of forum members.

I can get the Sonoff POW R2s to Tygervalley (transport plus taxes) @$13 each if we bulk buy.
 

riscbroker

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Joined
Sep 29, 2006
Messages
1,907
I just use a Sonoff Basic with a loop timer set to delay the power resumption to my fridge. Works fine.
 

ghostim

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Joined
Dec 27, 2004
Messages
1,640
Looks interesting. Some of the Tuya devices can be flashed with Tasmota.
 

Dairyfarmer

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Joined
Apr 17, 2016
Messages
3,684
I saw quite a few posts on powerforum that the POW2 burns after a few months.
That is where people don't ensure a tight connection or use too small a gauge wire. My 3kw geyser pulls 15.8 amps at full tilt. If the wire is too thin then it will heat up. I found that the 20amp wire that I have from the DB to the geyser was too thick to go into the POW connections. So I used a thinner solid copper wire, that we use on some of our pump contactors, to connect the POW to 20amp strip connectors. These have holes big enough to accommodate the thicker 20amp wire. I also found that the screw down plate doesn't go down far enough with the 6 thick wires and it is easy to damage the terminals on the POW.
 

OCP

Expert Member
Joined
Jan 23, 2014
Messages
3,720
If you want to do a bulk order I did one last year with a couple of forum members.

I can get the Sonoff POW R2s to Tygervalley (transport plus taxes) @$13 each if we bulk buy.
Can vouch for Mr Handy Hammer + can bring stuff to the Southern Suburbs
 

SauRoNZA

Honorary Master
Joined
Jul 6, 2010
Messages
36,223
To be honest this is all a bit of the paranoia side of things and smartify’ing for the sake of it.

If your device was going to die due to a surge the odds are that it’s still going to die even with a Sonoff in between.

A lack of money all round for something that will likely never happen.

Rather up your insurance to cover such instances specifically for less money.
 
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