UPS for Ormerod 2

Hi all,

We are entering thunderstorm season here with lots of power outages so a few questions:

Besides the pain of having a print interrupted, what are the possible issues with power failures? My main concern is loss of power to the hot-end fan, with possible damage to printed parts around the nozzle as well as filament melting too far up the nozzle.

I therefore want to use a small PC UPS (around 600 VA) to keep the printer going through the short drops in power, as well as giving enough time to cool the nozzle and shut down the printer during longer outages.

Any comments on this would be appreciated

James

Hi James,

I have set up my printer to move to a certain point after printing and switch off the 12V power supply. This will result in the hotend not beeing activly cooled. I have not seen any problems with that. You will have problems keeping the heated bed at temperature. Your UPS will have to keep it at temperature because a small drop will cause the parts to come loose. At least for my printer this is.

I once had the problem that the gcode was not completely transmitted to the sd card so the print stopped mid print with the hotend right at the surface. It did not cause that much harm to the surface. The problem might be that you have to heat up the hotend after a power outage to get the cancled print off the nozle.

A 600VA UPS should do just fine and give you lots of time to do a controlled shutdown, but just to be on the safe side, print these parts as extras, you may need to change them anyway if you plan to print ABS in the future: nozzle-mount, heat sink duct, fan duct, x-carriage



Erik

Thanks for the feedback guys,

Erik, I am indeed planning on printing these parts as soon as calibration is complete. I see the hotend fan duct has been eliminated from the latest spec of the Ormerod 2 and replaced with laser cut acrylic part. I am seriously considering going that route. But since I will be printing with ABS at some point the others will come in handy as well.

James

Quote
ormerod168
...A 600VA UPS should do just fine and give you lots of time to do a controlled shutdown..

..and if you UPS's backup battery is 12v lead as the one I have (APC) then you can extend the up time by changing that for a bigger one, e.g a 60Ah standard car/tractor battery, just be careful with high amp, ad a fuse to protect the UPS and cabling

Erik

Instead of going to the expense of a UPS, you could buy a 12V lead-acid utility battery and a battery charger suitable for leaving on constant float charge, then do away with the mains PSU altogether and run the Ormerod directly from the 12V lead-acid battery. In most places in the UK there is more risk of the invertor part of a small UPS failing than the grid mains failing, so using a UPS actually *increases* the risk of a power outage.

Dave

Quote
dmould
Instead of going to the expense of a UPS, you could buy a 12V lead-acid utility battery and a battery charger suitable for leaving on constant float charge, then do away with the mains PSU altogether and run the Ormerod directly from the 12V lead-acid battery. In most places in the UK there is more risk of the invertor part of a small UPS failing than the grid mains failing, so using a UPS actually *increases* the risk of a power outage.

Dave

Yes, agree Dave, this is my ideal solution for here in Cornwall in the UK where we get quite a few outages over the winter, many for a few seconds to minutes, presumably as everything resets after a short in the high winds?
I was thinking of a Solar panel or golf cart type 12V sealed battery allowing a short period of operation. The problem to date has been finding a suitable charger, many seem to do fancy things with the charge voltage, but I'm sure there is a simple solution lurking out there.....

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Ormerod #007 (shaken but not stirred!)

Treth a Solar or golf cart battery would be a good choice for longer running periods as they are deep cycle and can be discharged to a greater degree than car type batteries .Almost any charger would do as long as it has overcharge protection.Solar chargers tend to do a lot with charge voltage as you say as to be efficient they must convert high voltage from the panel ( as high as 17 v for a "12v" panel at peak times) to a safe charge voltage by Increasing the current produced.
You have all got me rethinking the UPS. I Originally intended to just keep the printer going through short drops in power and shutdown safely in longer outages,but I have a larger invertor/charger that needs a new battery.I think I will replace that and have enough capacity to finish a longer print. A few days ago we had a disaster at one of the countries largest power stations and it seems 4 hour rolling blackouts are going to be a possibility until repairs are complete!