UPS Query.

Renny

Padawan
Config:-

FSP Saga II 500W SMPS
AMD Athlon 64 3000+ (2.0GHz)
MSI K8MM-V Motherboard, 2x80mm Fans
2x1 GB DDR1 400MHz RAM
Geforce 7300GT CPU (AGP)
Benq G2222HDL Monitor
LG CD/DVD Writer
Seagate 1TB HDD (7200.12, SATA)
PS/2 Keyboard and Mouse
DLink DWA-125 USB WiFi Adapter
Windows 7 Ultimate (32-bit)

No plans to add any future hardware except a Blu-Ray Writer, and another SATA HDD(2TB),

I need the UPS just to shutdown the PC as soon as the power goes, nothing else,

Would a APC 600VA UPS suffice? Or any other suggestions?
 
Last edited:

pimpom

Cyborg Agent
Your system is not power-hungry even with the future additions. Power consumption will probably not exceed 200W peak, much less at idle or light usage. IIRC the 600VA APC is rated for ~360W. So you can put your mind at ease and use the APC 600VA UPS.
 

pimpom

Cyborg Agent
First, it's not that 600VA equals 360W. It means that the UPS has different ratings for different conditions.

With DC, voltage and current always flow at the same time. In this case, voltage x current = power, or VA = P (in Watts).

With AC, the voltage is constantly changing in value and direction. If the load is resistive like an incandescent light bulb or a simple heater, then the current changes in sync with the voltage. In this case, VA = P as with DC.

However, with many types of AC load, e.g., motors, electronic products, etc., the current does not vary in sync with the voltage. The current is said to be out of phase with the voltage. In such cases, VA is not equal to P. In certain cases, we may have a considerable amount of voltage and current in the same circuit but zero power!

The ratio of power to volt-amperes is called the power factor. Thus P.F. = P/VA.

Power sources (generator, UPS, etc.) have maximum amounts of voltage, current and power that they can withstand. And since VA is not always equal to Power, we have to have separate ratings for VA and power.

I've tried to present a general picture so far. A more detailed explanation will involve some maths and diagrams. It's 3:30 AM now and i have to go to bed. Maybe we can continue later. You can also do some research yourself by reading about power factors.
 

jerrin_ss5

Never give up!!
First, it's not that 600VA equals 360W. It means that the UPS has different ratings for different conditions.

With DC, voltage and current always flow at the same time. In this case, voltage x current = power, or VA = P (in Watts).

With AC, the voltage is constantly changing in value and direction. If the load is resistive like an incandescent light bulb or a simple heater, then the current changes in sync with the voltage. In this case, VA = P as with DC.

However, with many types of AC load, e.g., motors, electronic products, etc., the current does not vary in sync with the voltage. The current is said to be out of phase with the voltage. In such cases, VA is not equal to P. In certain cases, we may have a considerable amount of voltage and current in the same circuit but zero power!

The ratio of power to volt-amperes is called the power factor. Thus P.F. = P/VA.

Power sources (generator, UPS, etc.) have maximum amounts of voltage, current and power that they can withstand. And since VA is not always equal to Power, we have to have separate ratings for VA and power.

I've tried to present a general picture so far. A more detailed explanation will involve some maths and diagrams. It's 3:30 AM now and i have to go to bed. Maybe we can continue later. You can also do some research yourself by reading about power factors.
oh that's an interesting fact but i didn't understand how ups parameters are measured to watts?
 
OP
Renny

Renny

Padawan
Thanks for your suggestions, how good is Numeric 600VA? Any other cheaper UPS which would be comfortable for my config?
 

dashing.sujay

Moving
Staff member
First, it's not that 600VA equals 360W. It means that the UPS has different ratings for different conditions.

With DC, voltage and current always flow at the same time. In this case, voltage x current = power, or VA = P (in Watts).

With AC, the voltage is constantly changing in value and direction. If the load is resistive (wtH resistive load is :| ) like an incandescent light bulb or a simple heater, then the current changes in sync with the voltage. In this case, VA = P as with DC.

However, with many types of AC load, e.g., motors, electronic products, etc., the current does not vary in sync with the voltage. The current is said to be out of phase with the voltage. In such cases, VA is not equal to P. In certain cases, we may have a considerable amount of voltage and current in the same circuit but zero power! how ?:-o

The ratio of power to volt-amperes is called the power factor. Thus P.F. = P/VA.

Power sources (generator, UPS, etc.) have maximum amounts of voltage, current and power that they can withstand. And since VA is not always equal to Power, we have to have separate ratings for VA and power.

Once again thnx pimpom for your good electrical concept explanation :thumbs:

Queries-
1) I read online about PF, tell me what in AC circuits causes P =! VA ?
2) Explain the highlighted lines.
3) So, basically, Power is the most important thing one has to keep in mind while buying a UPS?
4) Why don't PSU's have also a separate VA and power rating ? (sry if i sound n00b)

TIY

Thanks for your suggestions, how good is Numeric 600VA? Any other cheaper UPS which would be comfortable for my config?

Numeric is a good brand, but if you real want cheap UPS's, you can go for intex/microtek ones. I'm using a intex greenX 600, and its working fine for me.
 
OP
Renny

Renny

Padawan
Sorry for bumping an old thread-------------


I need to buy another UPS for a similar config(everything is same except as the above config except its a P4 with 865P chipset, 7300GT AGP), but my budget is lower, how good is Zebronics, iBall, Matrix (600VA ones)?

And the other system has a Dell ST2220L monitor, would a 600VA UPS be enough to support both the the monitor and system?

Requirement is just 5-10mins to shutdown the PC.
 

casual_gamer

In the zone
Config:-

FSP Saga II 500W SMPS
AMD Athlon 64 3000+ (2.0GHz)
MSI K8MM-V Motherboard, 2x80mm Fans
2x1 GB DDR1 400MHz RAM
Geforce 7300GT CPU (AGP)
Benq G2222HDL Monitor
LG CD/DVD Writer
Seagate 1TB HDD (7200.12, SATA)
PS/2 Keyboard and Mouse
DLink DWA-125 USB WiFi Adapter
Windows 7 Ultimate (32-bit)

No plans to add any future hardware except a Blu-Ray Writer, and another SATA HDD(2TB),

I need the UPS just to shutdown the PC as soon as the power goes, nothing else,

Would a APC 600VA UPS suffice? Or any other suggestions?

Your system is not power-hungry even with the future additions. Power consumption will probably not exceed 200W peak, much less at idle or light usage. IIRC the 600VA APC is rated for ~360W. So you can put your mind at ease and use the APC 600VA UPS.

if his power consumption will not exceed 200w even during peak period, will a 250w psu not be enough instead of his FSP 500w?
 
Top Bottom