Selection Of Types Of RCD

RCD's exist in various different forms and react differently depending on the presence of DC components or different frequencies.

The following RCD's are available with the respective symbols and the designer or installer is required to select the appropriate device for the specific application.


RCD Testing

Type AC

General purpose use, RCD can detect & respond to AC sinusoidal wave only.


Type A

Equipment incorporating electronic components RCD can detect & respond as for type AC, PLUS pulsating DC components.


Type F

Equipment with frequency controlled speed drives RCD can detect & respons as for type A, PLUS high frequency residual current.


Type B

Electric vehicle chargers, PV supplies.

RCD can detect & respond for type F, PLUS smooth DC residual current.


RCD's & Their Loads


Types of Load       

Type AC                 

Resistive, capacitive, inductive loads
Immersion heater, oven / hob with resistive heating elements, electric shower, tungsten / halogen lighting

Type A

Single phase with electronic components
Single phase inverters, class 1 IT & multimedia equipment, power supplies for class 2 equipment, appliances such as washing machines, lighting controls, induction hobs & EV charging

Type F

Frequency controlled equipment
Appliances containing synchronous motors, some class 1 power tools, some air conditioning controllers using variable frequency speed drives

Type B

Three phase electronic equipment
Inverters for speed control, ups, EV charging where DC fault current is >6mA, PV




More from the 18th Edition

Surge Protection

A transient overvoltage or surge is a short duration increase in voltage measured between two or more conductors. In short this means anything from microseconds (millionths of a second) to a few milliseconds (thousandths of a second) in duration.

Read more


Arc Fault Detection Devices

Arc fault protection devices (AFDD) use microprocessors to identify characteristic current flow and voltage curves that indicate an arc fault and automatically trip the affected circuit.

Read more


Overload Protection

Devices such as switches, RCCBs etc. in distribution boards and consumer units may have historically had their rated current determined after having taken diversity into account but without having considered overload protection of the devices.

Read more


BEAMA Guides

A collection of the latest guides relating to 18th Edition, Hager is proud to be a technical contributor to these guides which provide technical advice on a range of 18th Edition related topics.

Read more

Related Products

Check out our product solutions for Type A RCDs below.


We have a wide range of RCCBs in Type A.



We have a wide range of RCBOs available in Type A.