WEE Technology Company Limited - WEE are Capacitors Specialist

What is the Difference Between Metallized Polyester Film CL Capacitors and Metallized Polypropylene Film CBB Capacitors

Polypropylene film capacitor is an inductive structure, which is made of polypropylene as dielectric and aluminum foil as electrode. The conductor is tinned copper clad steel wire and epoxy polypropylene film capacitor is used.

Characteristics of Polypropylene Film Capacitor:

• Small volume and light weight;

• Better stability and reliability.

• The lead wire is directly spot welded to the electrode with low loss.

• It is widely used in the DC and pulse circuits of TV sets, radio recorders, DVD and various communication equipment and electronic instruments.

Polyester film capacitor is also known as CL capacitor, and polypropylene film capacitor is also called CBB capacitor. The two types of capacitors are well differentiated from each other.
Generally, polyester film capacitor starts with CL, while polypropylene film capacitor starts with CBB. Both of them have the characteristics of self-healing and insensibility.

The main differences between CL and CBB are as follows:

1. The stability of CBB capacitor is higher than that of CL capacitor at high frequency.

2. Under the same temperature change condition, the range of CBB capacitance changing with temperature is smaller than that of CL capacitance.

3. The loss of CBB capacitor is smaller than that of CL capacitor. At the frequency of 1kHz, the tan δ of CBB capacitor is less than 0.001, while that of CL capacitor is less than 0.01.

4. The insulation performance of CBB capacitor and Cl capacitor is particularly good, which is better than other capacitors, while the insulation performance of CBB capacitor is better than that of CL capacitor. For example, when the capacity is less than 0.33uf, the insulation resistance of CBB capacitor is greater than 25000 m Ω, while that of CL capacitor is greater than 7500 m Ω.

5. Compared with CBB capacitor, CL capacitor  has the advantage of small volume. Under the same voltage and capacity, the volume of CL capacitor can be smaller than that of CBB capacitor, which is very useful for customers with limited installation space.

As CBB capacitor has better performance, but its price is more expensive, so there are many CL capacitors in the market that can not be found out by visual inspection. Therefore, Zongqiang Electronic Engineer recommends the following two methods for your reference:

1. Measure the loss value. If it is less than 0.001, it is CBB capacitor, otherwise it is CL capacitor.

2. Conduct the test with palm digital capacitance meter and hair dryer. First, put the capacitor on the capacitance meter to measure the cold state capacitance value, then heat the capacitor with the air blower, and then measure the capacitance value. If the capacitance value changes too much, it is CL capacitor, otherwise it is CBB capacitor