500VA Control Transformer Model: RBK-500
Selection of Toroidal Transformer
Toroidal Transformers offer many advantages over standard laminated power
transformers. Toroidals provide quiet, efficient operation with very low stray magnetic
fields. Their small size and weight support a package that is easy to design into any
application.
Advantages of Toroidal Transformer:
How to find VA for Transformers
Volt amps (VA) is the effective power rating for a transformer. In the perfect transformer,the voltage and current (combined) applied at the primary will exactly equal the voltage and current (combined) on the secondary(s).
Efficiency is measure of a transformer’s ability to delivery the input power to the load. Efficiency is expressed as a percent by:
% = ( PO / PI ) X 100 (Where: PO = Output power, PI = Input power, % = Efficiency)
VA Calculation
1.Read the transformer’s secondary winding rating (printed or tagged on the transformer case). This should give a rating such as 5V, 500mA.
Multiply the voltage times the current to receive the VA.
Example: 5V times 500mA (or 0.5A) equals 2.5VA
2.Convert the secondary winding VA value to the primary winding VA rating as the equation VA (Primary) equals VA (Secondary) or VA (p) = VA(s)
For example of a 2.5VA secondary, if the primary voltage is 120V the current will be A (p) =VA(s) / V(p). Giving A(p) = 2.5 / 120 = 0.020833 (roughly 21mA).
This is the calculation for a single input winding/single output winding transformer.
3.Add the separate VA ratings for a transformer with multiple secondary windings.
For secondary winding 1 = 5VA at 500mA
Secondary winding 2 = 24V at 100mA
Total Secondary VA = ( 5 X 0.5 ) + ( 24 X 0.1 ) = 4.9VA
Primary VA will still equal the total secondary VA.
Item | Capacity | Voltage Combination | Case Qty. |
Model | (VA) | Primary (V)/Secondary (V) | (Pcs) |
RBK-50 | 50 | 440/220;240/24;220/24; 220-380/110-60-48-24, 380/220-110 | 24 |
RBK-100 | 100 | 24 | |
RBK-150 | 150 | 16 | |
RBK-200 | 200 | 12 | |
RBK-250 | 250 | 6 | |
RBK-300 | 300 | 6 | |
RBK-400 | 400 | 4 | |
RBK-500 | 500 | 4 | |
RBK-700 | 700 | 1 | |
RBK-1000 | 1000 | 1 | |
RBK-1500 | 1500 | 1 | |
RBK-2000 | 2500 | 1 |
Note:
Please mention the voltage combination when ordering. Other else multiple voltage combination upon request.
1. Experienced manufacturer more than 10 years.
2. Highly experienced production team in YOMIN factory work-shop.
3. QC Systerm: Quality controlled on all production lines, and QC inspectors work independently from the production line.
4. Good quality production with quick delivery.
5. Accepted OEM/ODM.
6. Accepted small MOQ.
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