32

You need an inlet in Room A, not an outlet You'll need an outlet box with an inlet in it in Room A so that you can plug the output of the UPS into it with a proper cord (read: if you have to do weird crap to your cord to plug the output of the UPS into the wall, stop, because that's a sign you're doing it wrong!). From there, you can use a suitable chapter ...


11

We see a lot of really horrid transfer switches on this forum, believe you me. The Backup Generator Subpanel (Siemens - gray panel) is my "economic" version of a Transfer Switch, with a mechanical interlock between the upper "30A generator" breaker and the lower "30A subpanel feed" breaker. What you did there is absolutely ...


8

Two identical 12V car batteries could deliver 24V, and two identical 120V~ transformers at the same net could deliver 240V~. But two 120V~ generators can not simply be connected in series to get 240V~. They must have a special interface/circuit to offer that option, because both generators must be locked to exactly the same frequency and must be locked to ...


6

Measuring the startup load is as easy as using a clamp on meter and turning the air handler on and off. The startup load will be high for a split second, then drop down to a steady load. Use Ohms Law to calculate the wattage. Watts/Voltage = Current As mentioned in my comment, the invertors peak load is a good indication of the invertors motor starting ...


5

I have a feeling you will find this to be quite a bit more involved than you originally expected. In addition to whatever other code issues involved in setting up a power "inlet" in Room A (as opposed to the normal receptacle = "outlet"), at a minimum you would need to use approved wiring methods to get from Room A to Room B. That means Romex properly ...


5

Buy a (petrol-fired) air compressor and pneumatic tools, or go for a bigger generator. (Good) Inverter can cost nearly as much as a generator, also remember that an inverter rated for 2kW has a substained rate of about half. I found on Amazon this 3kW inexpensive inverter, check if it may be good for you. Anyway, with an inverter it's important that the ...


5

A regular consumer UPS will keep the voltage within acceptable limits for electronic equipment, but it won't do much cleanup of electrical noise or irregular frequency while it's powering the equipment from the mains power. That's because they're designed to supply mains power as long as it is available. The battery kicks in only if the mains power goes ...


4

Ask your local regulatory agency. They will probably have that information. However, the usual practice for anything but critical servers is to decide how long you will need to finish what you were working on, save it, and shut down cleanly. If you really want to run for many hours, the simplest answer is just to use a laptop machine. They are designed for ...


4

Not wishing to state the obvious, but really, the first thing to do is resolve the power fluctuations if at all possible. Assuming that's out of your control, then a decent UPS should be able to handle this by itself. You shouldn't need external inverters or stabilisers. To be honest, at first glance, it sounds like your initial UPS may be faulty or ...


4

No "checklists"! Hard-built interlocks only. There is no such thing as "making sure your main breaker and 2-pole breakers are turned off". You must not do generator interlocking via a checklist or procedure. There are only three legitimate ways to switch from mains to backup power: a generator-style interlock or transfer switch "permanently" rewire ...


4

You want an automatic transfer switch The device you want is called an automatic transfer switch (ATS for short) and should be readily available through an electrical supply house (or equivalent) in your area. Note that this device will need to be approved by your local electrical authorities. A proper ATS not only has electrical protection, but ...


4

Doesn't work. They're not in phase This is part of why Thomas Edison hated AC power. It's very hard to understand, what with the flux vectors, phasing and all that jazz. Tesla was a genius, and Edison was merely persistent. The upshot is that 240V is a single source with a center-tap (giving 120V each direction of center. In fact, when Edison designed it, ...


3

You can't average the monthly usage over a number of days because the loads aren't constant. Consider the following two scenarios: A 100W light bulb that's turned on constantly for the whole month (30 days). This uses 100W * 24hr / day * 30 day / month = 72 kWh for the month. A 2400W heater that runs one a day for an hour. This uses 2400W * 1hr / day * 30 ...


3

AC power cannot be stored because AC is dynamically changing (to be more precise, alternating). It requires very expensive hardware to arbitrage it for other types of energy which are storeable, and in the sizes you need, the cost of that hardware is well beyond the scope you established in your question. That leaves: Hand tools. Exercise your arms. ...


3

Yes. You are allowed to use standard practices for in-wall wiring to build a "runt circuit" that goes A to B to C to D and does not actually go to any service panel. You fit standard outlets in all locations but exactly one. Since there are no other inlets, you fit one inlet capable of taking an extension cord. Every circuit needs some number of ...


3

The images in the eBay post show a 12v 7a power supply with a pinout on the power brick. The pinout shows only a 12v positive (pin) and ground (barrel). The connector is called a 4P Power Snap and Lock, but you may also find it loosely described as a 4 pin DIN connector. The latter description is slightly inaccurate. If you have a volt meter, you can ...


3

If the neutral is just a straight wire through the UPS, and it almost certainly is, then this would have no effect. If not, then this would be a very bad idea. I wouldn't connect the neutral at all. (Of course, this may be a bad idea for other reasons, not the least of which is it would certainly violate code.)


3

The battery is dead Sandy was 2012 and 7 years is better than average for a starting battery. Given that this is emergency equipment, you really ought to replace it prophylactically well before that. Basically the weak battery is acting like a capacitor. That's why it shows voltage while and just after it's on the "battery tender". Also 12.3 V is very ...


3

The trouble with back-feeding portable generator power through any of those welding or RV plugs while the transfer switch is set to generator position is the same problem with relying on turning off the main breaker before doing the same: it's manual, not interlocked, and sooner or later somebody is going to get it wrong. Instead, daisy-chain another ...


2

When temporarily testing things... Just take box covers off and wire-nut stuff. My cheater is male on one end, bare wires on the other. I just go into the box, wire-nut up the load under test, plug the cheater into the Kill-a-Watt or whatever, and do my testing. Easy peasy. I test hardwired loads that way all the time, it's no big. Don't bottom your ...


2

It's a heavy load like an air conditioner, so use an air conditioner extension cord. Manufacturers can be greedy/cheap about sizing extension cords, using the absolute minimum UL requires for safety. Bumping to the next size could cost them 25 cents a unit wholesale, which on 100,000 units, is real money. Using a same-gauge extension cord is not a good ...


2

You have what you need. That box or every one I have ever seen are listed for outdoor use. I would open your transfer switch, find a handy spot and drill a hole through the wall install a bushing or short piece of conduit to connect the transfer switch to the inlet and secure the inlet box. I will use caulking around the bushing or nipple to seal it up.


2

Lithium battery inverters are very good for this - if you have the budget. They are not inexpensive. Other battery chemistries are more problematic from a lifetime or percent of supposed capacity that's actually usable point of view, and become not-inexpensive themselves when you account for the oversize needed to deal with those factors. 350 watts for 24 ...


1

You would need a weather tight box, and a cover that would allow your cord cap (plug) to be connected WHILE it is raining, so usually with a built-in double lipped rubber seal arrangement where the cord cap and inlet cover are matched. Your cord itself would need to be what's called "portable cord", usually type SJOW, and the connection to the cord cap would ...


1

As mentioned in comments, typical inverter switch times are fine for most devices. The only way I know of to literally have NO downtime is dual-conversion, where your inverter is supplying the AC power 100% of the time, and your grid power is converted to DC and fed into the battery / DC input of the inverter. That has built-in inefficiencies (thus, wasted ...


1

To use a UPS located in one room for equipment located in another room, you need a UPS designed to be hardwired. This is called a Structured Wiring UPS, and they are typically prohibitively expensive. They have internal wiring connections that an electrician would connect circuit breakers and then outlets to. They do not have normal outlets on them that you'...


1

What they're referring to here is a ground rod Generally speaking, AC mains electricity in the US needs to be earthed (grounded), with the neutral and protective earth (ground) wires bonded to each other and to a grounding electrode system at the main service entrance, to keep the mains from rattling off to some high voltage relative to other grounded ...


1

Turns out that for my thermostat, I think I had to wait a bit longer. It took around 10-15 minutes for the display to completely go blank after the breaker was turned off. I think it might have been a large capacitor contributing to this issue, and it was taking a very long time to discharge.


1

Your PC power supply is the issue The problem is your PC power supply is extremely sensitive to brownouts. That's a bit hard to understand, since most PC power supplies are world voltage 100-240V (dynamically; they buck the voltage down to their working voltage) and your power is normally 220. A good PC supply should "ride the brownout" down as low as ...


1

Your UPS seems expansive enough that it might have its own logs. See if its AVR kicks in when the fluctuations happened (if you're not there yourself.) Alternative, you seem to have enough money to get a battery powered oscilloscope. My guess is your UPS probably has a subpar or incorrectly calibrated AVR, which probably explains why if effs up on some ...


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