HBSM

The selection should be done after derating the Circuit Breaker taking into consideration voltage variation and capacitors tolerances that could increase nominal current up to 1.5In.

The Derating factor of 1.5In

Where In = Q/ ( Square root of 3 ) Un
Q = Capacitor Power
Un = Nominal Voltage

Choose the Micrologic with delay time selection, so that the Circuit Breaker does not trip due to initial high inrush current.

Also to be taken into account are the parameters like supply frequency, operating voltage & harmonics level of the power system for such application.

Refer the attached sheet for further details for selection of Circuit Breaker for Capacitor duty application.

Note: Use the phase barrier between the phases in Circuit Breaker to prevent flashover due to heavy inrush current.

Differentiations between these two series are concluded in the following:
1) Enclosure material
HBSM: Steel
HDCAP3: Aluminum
2) Capacity
HBSM: 0.5~60kvar
HDCAP3: 1~30kvar
3) Connection method
HBSM: Single-phase, three-phase, three-phase four-wire
HDCAP3: Three-phase
4) Rated voltage
HBSM: 230V, 250V, 280V, 400V, 415V, 440V, 450V, 480V, 525V, 660V, 690V
HDCAP3: 400V, 450V, 525V
5) Appearance
HBSM: Box type
HDCAP3: Cylinder type

Explosion-proof design works as below:
(1) Various breakdowns happened;
(2) Polypropylene metallized film is decomposed to produce gas under high temperature;
(3) A great amount of gas is unable to be released to increase the pressure inside the capacitor;
(4) The explosion-proof device is pulled to the left and right sides to make the enclosure be deformed as the       inner pressure is increasing.

Main conditions are as follows:
(1) Load connection: rectifier, VSD, soft starter
(2) Grid environment: refining, chemical industry, cement, electroplating
(3) Main order of harmonics: 5th, 7th, 11th
(4) Specified capacitor switching contactor is replaced by commercial AC contactor: easy to shorten lifecycle of       capacitors due to inrush current suppression ability (capacity reduction risk)