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Conditioned Power


On the heels of my previous questions. Is there a way to condition power coming into a single room without using point-of-use items? In other words can I connect something to the power line coming into the room? I am planning a media room and would like to keep an eye on that power. Thanks!


Re: Conditioned Power

You can buy a larger UPS set it near your breaker box and connect the line to it and the UPS to the breaker. In fact you can get Uninterpretable power supplies large enough to condition the power for the whole house.

Re: Conditioned Power

You can buy a larger UPS set it near your breaker box and connect the line to it and the UPS to the breaker. In fact you can get Uninterpretable power supplies large enough to condition the power for the whole house.

Yup, I set our office up to back 10 PC's this way with a 6kW UPS.

I got the UPS for free and replaced the battery string in it.

Re: Conditioned Power

If you are concerned with the power for your home theater set up .... running a dedicated isolated grounded circuit would be a start.
This will be dedicated for the receptacles which your electronics will plug into .... isolated from any other items such as lights etc..

While this helps it doesn't guarantee issues from the supply panel .... inherent noise and fluctuations from normal things like A/C units , washers , etc..

Including a device for filtering and conditioning the power for the serious home theater will help with this.

As previously mentioned ....... an uninterpretable power supply ( UPS ) can be considered for the electronics..... though the battery back up power is really not the main concern .... some can offer power conditioning.

Generally there are 3 types of UPS systems :

standby (offline) .... Normally, power reaches loads directly from its source. During a power failure, a switch connects a backup battery to the load, with a short, distinct power interruption.

  • In "normal " mode there is really no conditioning and only provides surge protection the same as a power strip.
  • Only when the battery powered inverter is active is when there would be any conditioning available ..... these I would not recommend.

Online ...... provide load power at all times through a battery that is continuously charged by input power. The battery is always online; therefore, no switching is called for during power failures.Online UPSs provide complete protection and isolation from almost all types of power problems and provide digital-quality power that is not possible with offline systems. For these reasons, they are typically used for critical applications that demand high productivity and systems availability.

  • "Double-converter system" is another name for an online UPS since it must convert AC input power to DC for charging the battery and afterward convert DC to AC for use by the load. Double conversion makes this UPS less efficient than other types.
  • Online systems provide the same benefits of an offline UPS combined with a line conditioner.

Line-interactive ..... retain some of the efficiency of offline UPSs while providing the voltage regulation features of online systems. Instead of converting the input power to DC and storing it in a battery, the UPS sends the power to the load through a ferroresonant transformer that provides voltage regulation and power conditioning for disturbances such as electrical line noise.

Sizing .....

Obtain the wattage rating of each device. This rating should be listed on the equipment nameplate or in the owner‘s/operator’s manual or available from the equipment manufacturer.

If specified in VA, multiply the VA by 0.85 to determine the watts. If given in amps, multiply the amps by 102 to obtain watts.

Add the total wattage ratings for all devices to be protected .
Choose a UPS unit with a wattage rating equal to or greater than the total wattage requirements.

Example ....... If you have determined the demand to be 1,100 watts and the brand of UPS you have selected has only a 1,000-watt unit with the next model rated at 1,300 watts, select the 1,300-watt system.

Now having said all that .... there are some considerations associated with these systems.

Depending on the type and size the UPS must be installed with adequate ventilation for maintenance and operation. There will also be the battery replacement costs and handling .

Another option to consider is the power conditioning devices that can be purchased
at a retail outlet.

While not promoting or endorsing this product here is an example....

This type of equipment is designed to provide a constant voltage supply and provide conditioning by employing circuitry using a constant voltage transformer ( CVT ) along with filter components.

Just a thought. :)

Re: Conditioned Power

Good Call Canuk. I think once he see's what it will cost to have a UPS for all his electronics he will soon just use a surge protector;)

Re: Conditioned Power

Canuk's description is very comprehensive. An Online UPS provides the greatest protection and completely isolates the equipment from the line. I have seen direct lightening hits that have blown the front end of an online UPS but all the equipment on the output was unaffected.
Stay away from CVTs (constant voltage transformers) like those sold at industrial supplies. Although they are very good at maintaining a set voltage during brown outs the have a tendency to go into a state of harmonic imbalance if there is any change in frequency (60HZ) which can be worse than low voltage and they provide very little conditioning other than voltage level.

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