Tedss.com logo.

Discount Electronic Components

Tedss.com text.
Need assistance? Give us a call. (631) 234-3857

Computer Grade Capacitors - Finding The Right Capacitor

If you are looking for a large capacitance (above 500 mfd) or a high voltage (up to 500 Volts) capacitor then you are probably looking for a large can electrolytic capacitor, commonly referred to as a computer grade capacitor.

If the part you are replacing begins with one of the following series, you are looking for a large can electrolytic capacitor, usually identified by having two screw terminals (a high post has an insulator off the top of the can).

Picture of Computer Grade Capacitor Picture of Computer Grade Capacitor Picture of Computer Grade Capacitor Picture of Computer Grade Capacitor Picture of Computer Grade Capacitor

How to read Computer Grade Capacitors?

How to read Computer Grade Capacitors?

Popular series of large can electrolytics capacitors.

  • CGS (85C computer grade standard)
  • CG (85C long life computer grade)
  • CGR (105C computer grade high temp)
  • CGO (85C computer grade low leakage)
  • DCMC (85C computer grade low ESR)
  • DCM (85C computer grade low ESR high ripple current)
  • Type 500 (85C computer grade long life)
  • Type 100 (105C computer grade low ESR)
  • Type 101 (105C computer grade low ESR)
  • 36D (85C computer grade standard)
  • 36DX (85C computer grade standard)
  • 23A (85C computer grade standard)
  • 23M (85C computer grade low ESR high ripple current)
  • 3186 (85C computer grade standard)
  • 3188 (105C computer grade long life)

Typically large can computer grade capacitors will have a capacitance measured in microfarads (mfd) or the designation uF. This capacitance is represented in numbers (example 10,000 mfd or 25,000 uF). Next you will see a voltage on the unit, designated by a V or WVDC (working voltage). 99% of the time, these capacitors are measured in DC (direct current) voltages. This is the constant voltage these capacitors will withstand.

Important in replacing these capacitors is not only the capacitance and voltage but also the size of the unit. The diameter of these capacitors comes primarily in the following diameters (in inches):

  • 1.375 (1 3/8)
  • 1.750 (1 3/4)
  • 2.0
  • 2.5 (2 1/2)
  • 3.0

In most cases these large can electrolytic capacitors are mounted to either board or chasis with round clamp VR series.

95% of the cans will fall into these categories. The height of the units can vary from 2.125 to 8.75 inches.

An important piece of information about large can electrolytics is their tolerances. Typically voltages from 6 volts to 150 volts have a tolerance of -10% +75%. This is important because a capacitor of 10,000 mfd at 50 volts can, in actuality, read on the positive side up to 17,500 mfd and be within tolerance. So when choosing a replacement capacitor, typically you have the flexibility to choose a mathematically suitable replacement. Above 150 volts up to 450 volts the typical tolerance is -10% +50% again, giving you flexibility when choosing a computer grade capacitor replacement.

These capacitors typically come with a PVC insulating sleeve.

Sizes of computer grade capacitors.

Diameter Length Spacing Mounting
Bracket
inch mm inch mm inch mm
1.375 35.0 2.125 54.0 0.5 12.7 VR-3
1.375 35.0 2.625 67.0 0.5 12.7 VR-3
1.375 35.0 3.125 79.4 0.5 12.7 VR-3
1.375 35.0 3.625 92.0 0.5 12.7 VR-3
1.375 35.0 4.125 105.0 0.5 12.7 VR-3
1.375 35.0 4.625 117.5 0.5 12.7 VR-3
1.375 35.0 5.125 130.0 0.5 12.7 VR-3
1.375 35.0 5.625 143.0 0.5 12.7 VR-3
 
1.75 44.5 2.125 54.0 0.75 19.0 VR-6
1.75 44.5 2.625 67.0 0.75 19.0 VR-6
1.75 44.5 3.125 79.4 0.75 19.0 VR-6
1.75 44.5 3.625 92.0 0.75 19.0 VR-6
1.75 44.5 4.125 105.0 0.75 19.0 VR-6
1.75 44.5 4.625 117.5 0.75 19.0 VR-6
1.75 44.5 5.125 130.0 0.75 19.0 VR-6
1.75 44.5 5.625 143.0 0.75 19.0 VR-6
 
2.0 50.8 2.125 54.0 0.875 22.23 VR-8
2.0 50.8 2.625 67.0 0.875 22.23 VR-8
2.0 50.8 3.125 79.4 0.875 22.23 VR-8
2.0 50.8 3.625 92.0 0.875 22.23 VR-8
2.0 50.8 4.125 105.0 0.875 22.23 VR-8
2.0 50.8 4.625 117.5 0.875 22.23 VR-8
2.0 50.8 5.125 130.0 0.875 22.23 VR-8
2.0 50.8 5.625 143.0 0.875 22.23 VR-8
 
2.5 63.5 3.125 79.4 1.125 28.58 VR-10
2.5 63.5 3.625 92.0 1.125 28.58 VR-10
2.5 63.5 4.125 105.0 1.125 28.58 VR-10
2.5 63.5 4.625 117.5 1.125 28.58 VR-10
2.5 63.5 5.125 130.0 1.125 28.58 VR-10
2.5 63.5 5.625 143.0 1.125 28.58 VR-10
 
3.0 76.2 3.625 92.0 1.25 31.75 VR-12
3.0 76.2 4.125 105.0 1.25 31.75 VR-12
3.0 76.2 4.625 117.5 1.25 31.75 VR-12
3.0 76.2 5.125 130.0 1.25 31.75 VR-12
3.0 76.2 5.625 143.0 1.25 31.75 VR-12
3.0 76.2 5.876 149.0 1.25 31.75 VR-12
3.0 76.2 6.625 168.0 1.25 31.75 VR-12
3.0 76.2 7.625 194.0 1.25 31.75 VR-12
3.0 76.2 8.625 219.0 1.25 31.75 VR-12

Back to Top