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Unless paying out £90 plus or hiring a meter one is unlikely to get much better than the simple energy monitor. I have three plug in energy monitors odd but the more expensive versions tell you a lot less, OK you get a graph
but it rounds off the corners, so as far as inrush goes cheaper stand alone units are better. I use the energy meter to check the freezer is OK, the inverter drive easy, you see it is using around 60 watt, and when the defrost cycle cuts in you see the 180 watt as the heater turns on as a peak, but with the non inverter drive from memory the start amps is some where around 5 amps, as said varies, so I could not return to see if the defrost cycle was working. With the computer logged display I could, but no peak, power factor, etc, in fact a lot less than the cheap model.
As to clamp on meters, again it seems often the expensive one tell you less. My first clamp on I got when working in Hong Kong, it has frequency among other features, very handy to set up generators, but it does not measure DC amps, and only goes down to 0.01 amp which when I got it before the take over was good enough, but with the advent of 30 mA RCD's to measure to see if under 9 mA needs a 0.001 amp range, and today we also need to measure DC amps, so we need a better meter.
However the expensive fluke seem to have missed the point, and many still only go down to 0.01 amp, until your paying well over £100. Also to use a clamp on you need to access one conductor, either line or neutral, but not both, so to use them means some dismantling this is not really what we want the DIY guy to do, so the cheap plug in energy meter in this case is likely the best option.
OK if it says 4 amp consider really it may use 5 amp, but to get a 5 amp (1150 watt or VA) with pure sine wave output is as said before going to cost around £200, I am not sure if the simulated sine wave will work OK or not? It has an off bit
so not square wave, but nearly square wave, some things are OK other are not, and you don't what to buy twice.
It depends why you want to run a fridge off DC, I want my 4 freezers and my central heating to continue to work during a power cut, either a generator or an inverter will do, but the generator needs to be started and for some one to manually unplug from the normal supply and plug into the generator. Which if I check with my phone I can see if I have had a power cut, but it would be better if automatic.
But a 5 kWh battery will not last long, so the inverter may be OK for central heating, but if off long enough to need emergency power, then it would need a method to recharge the battery, in may case I have an array of solar panels, so just freezers and central heating should last until I get a dull day.
But we are not only looking at how to power a fridge, but also why, I can let my beer fridges warm up, I want it one when we have a BBQ but does not need to be one 24/7. It is easy enough to get a bottle of gas to keep the fridge cool, not so easy to take a battery to be charged. So best option depends on why you want to run it off grid.
but it rounds off the corners, so as far as inrush goes cheaper stand alone units are better. I use the energy meter to check the freezer is OK, the inverter drive easy, you see it is using around 60 watt, and when the defrost cycle cuts in you see the 180 watt as the heater turns on as a peak, but with the non inverter drive from memory the start amps is some where around 5 amps, as said varies, so I could not return to see if the defrost cycle was working. With the computer logged display I could, but no peak, power factor, etc, in fact a lot less than the cheap model.As to clamp on meters, again it seems often the expensive one tell you less. My first clamp on I got when working in Hong Kong, it has frequency among other features, very handy to set up generators, but it does not measure DC amps, and only goes down to 0.01 amp which when I got it before the take over was good enough, but with the advent of 30 mA RCD's to measure to see if under 9 mA needs a 0.001 amp range, and today we also need to measure DC amps, so we need a better meter.
However the expensive fluke seem to have missed the point, and many still only go down to 0.01 amp, until your paying well over £100. Also to use a clamp on you need to access one conductor, either line or neutral, but not both, so to use them means some dismantling this is not really what we want the DIY guy to do, so the cheap plug in energy meter in this case is likely the best option.
OK if it says 4 amp consider really it may use 5 amp, but to get a 5 amp (1150 watt or VA) with pure sine wave output is as said before going to cost around £200, I am not sure if the simulated sine wave will work OK or not? It has an off bit
so not square wave, but nearly square wave, some things are OK other are not, and you don't what to buy twice.It depends why you want to run a fridge off DC, I want my 4 freezers and my central heating to continue to work during a power cut, either a generator or an inverter will do, but the generator needs to be started and for some one to manually unplug from the normal supply and plug into the generator. Which if I check with my phone I can see if I have had a power cut, but it would be better if automatic.
But a 5 kWh battery will not last long, so the inverter may be OK for central heating, but if off long enough to need emergency power, then it would need a method to recharge the battery, in may case I have an array of solar panels, so just freezers and central heating should last until I get a dull day.
But we are not only looking at how to power a fridge, but also why, I can let my beer fridges warm up, I want it one when we have a BBQ but does not need to be one 24/7. It is easy enough to get a bottle of gas to keep the fridge cool, not so easy to take a battery to be charged. So best option depends on why you want to run it off grid.
