Manufacturer 800VA Toroidal Transformer ,Power Transformer . Quality Choice
USD $28.64 - $30.8 /Piece
Min.Order:1 Piece
Yueqing Yomin Electric Co., Ltd.
Manufacturer 800VA isolating transformer power transformer
Model: DH-800
Selection of Isolating Transformer
Isolating 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 Isolating Transformer:
1. A isolating transformer weighs about half as much as conventional transformer with the
same capacity and heat rise. The main materials used in transformer are copper and steel,
both of which are getting scarcer with cost increases as a consequence.
2. No impregnation is needed to keep the laminates quiet so this potential environmental
hazard is avoided.
3. The isolating transformer fits into a smaller space, which allows chassis plates and
enclosures to be smaller with less material used.
How to find VA for Isolating Transformers
Volt amps (VA) is the effective power rating for a transformer. In the perfect isolating
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 isolating 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 isolating 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 isolating transformer.
3.Add the separate VA ratings for a isolating 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 | Static Current | Efficiency | Voltage Combination | Case Qty. |
Model | (VA) | (mA) | (%) | Primary (V)/Secondary (V) | (Pcs) |
DH-50 | 50 | 10 | 90 | 230/24;220/24;230/36; 220/36;440/230;230/12; 130-240/15-240;115/24 | 24 |
DH-100 | 100 | 15 | 92 | 24 | |
DH-150 | 150 | 20 | 93 | 24 | |
DH-200 | 200 | 30 | 94 | 24 | |
DH-250 | 250 | 35 | 94 | 18 | |
DH-300 | 300 | 40 | 94 | 18 | |
DH-350 | 350 | 45 | 95 | 18 | |
DH-400 | 400 | 50 | 95 | 18 | |
DH-450 | 450 | 55 | 95 | 18 | |
DH-500 | 500 | 55 | 95 | 18 | |
DH-550 | 550 | 55 | 95 | 18 | |
DH-600 | 600 | 55 | 95 | 18 | |
DH-700 | 700 | 60 | 95 | 12 | |
DH-800 | 800 | 65 | 95 | 12 | |
DH-1000 | 1000 | 75 | 95 | 12 |
Note:
Please mention the voltage Combination when ordering. Other else multiple volage combination upon request.