Type B RCDs can detect sinusoidal AC, pulsating DC, composite of multi-frequency as well as smooth DC residual currents. Type B RCD are intended to be used for loads with three-phase rectifier, such as variable speed drives, PV system, EV charging station and medical equipment.

Type A Ensures tripping for residual a.c. currents and pulsating d.c. currents, Type B Ensures tripping for residual a.c. currents, pulsating d.c. currents and smooth d.c. currents.

30 ma RCD is not advisable on solar pv inverters. Most of the manufacturers recommend a 100 miliamp RCD. Just have that changed for a 100 miliamp rcd provided there are no socket outlets likely to supply an outdoor socket from the same circuit. The older your inverter gets the more leakage you will experience.

How do Type B RCDs work? Type B RCDs are usually designed with two residual current detection systems. The first uses ‘fluxgate’ technology to enable the RCD to detect smooth DC current. The second uses a technology similar to Type AC and Type A RCDs, which is voltage independent.

RCBOs type B grant protection to persons and machineries in presence of DC current and high frequency AC fault current. Among the several types of RCBOs, type B provide the upmost level of protection. RCBOs’ mechanism is trip-free, that is the RCBOs can also trip when the lever is held in ON position.

Type B circuit breakers are designed to trip if the current flowing through hits between three and five times the recommended maximum or ‘rated load’. This is the most sensitive type of MCB, designed for domestic applications, and low voltage commercial settings where any current surges are likely to be small.

In summary, RCD’s are only required to be installed on inverter circuits where they are needed to provide mechanical protection to the cables under AS3000 Clause 3.9. 4.2.

RCD Classifications

• RCCB. (Residual Current Operated Circuit Breaker without Integral Overcurrent Protection)
• RCBO. (Residual Current Operated Circuit Breaker with Integral Overcurrent Protection)
• SRCD. (Socket-Outlet incorporating a Residual Current Device)
• FCURCD.
• PRCD.
• CBR.
• RCM.
• MRCD.

Type AC devices can detect and respond to AC sinusoidal wave current only. Type A RCDs are used for alternating sinusoidal residual current and for residual pulsating direct current up to 6 mA. electric vehicle charging equipment with smooth residual DC current less than 6 mA.

every 6 months
Manufacturers are likely to recommend, therefore, that the button is pressed every 6 months.