4 Pole A-Type 100mA Time Delay RCD
The WCED A-Type 100mA Time Delay RCD is designed for installations requiring RCD selectivity between upstream and downstream devices – often referred to as RCD discrimination. With 100mA sensitivity and a built-in time delay, these devices help ensure only the correct breaker trips in the event of an earth fault,...
The WCED A-Type 100mA Time Delay RCD is designed for installations requiring RCD selectivity between upstream and downstream devices – often referred to as RCD discrimination. With 100mA sensitivity and a built-in time delay, these devices help ensure only the correct breaker trips in the event of an earth fault, keeping other circuits energised.
Built to BS EN 61008-1 standards and rated at 6kA, these RCDs are ideal for use in main incomer positions on distribution boards. They are commonly specified for EV charger installs, solar PV systems, and PME supplies where safe selectivity and discrimination are essential.
🧩 Available Variants:
- WARTD463-100: 4 Pole, 63A, 100mA Time Delay
- WARTD480-100: 4 Pole, 80A, 100mA Time Delay
- WARTD4100-100: 4 Pole, 100A, 100mA Time Delay
🔧 Key Features:
- Type A residual current detection – covers AC + pulsating DC faults
- 100mA sensitivity with built-in time delay (S-Type functionality)
- Prevents nuisance tripping in upstream devices
- Ideal for use in split-load consumer units or distribution boards
- Suited for EV charge points, solar installs, and PME systems
Looking for alternatives? For circuits needing combined overload and earth leakage protection, see our RCBO range, or for DC-sensitive protection, view our Type B RCDs.
What is a time delay RCD used for?
Time delay RCDs (S-type) are used in cascade configurations to prevent multiple devices tripping at once. The upstream RCD trips slightly slower, allowing the downstream device (e.g. RCBOs or 30mA RCDs) to isolate the fault first.
Is this suitable as a main incomer RCD?
Yes – 100mA delayed RCDs are commonly used as main incomers in three-phase boards or larger consumer units, with additional 30mA protection downstream.
What does Type A mean?
Type A RCDs detect AC faults and pulsating DC leakage, which is critical in modern installations with EV chargers, heat pumps, and solar PV gear.
Can I use this in an EV install?
Yes – it’s suitable for EV or solar installs where RCD selectivity and higher fault discrimination is required. Always follow the EV charger manufacturer’s guidance, and consider whether a Type B RCD is required instead.
Does it come pre-wired?
No — this is a standalone device and should be installed as part of a compliant consumer unit or distribution board setup.
- Poles: 4
- Sensitivity: 100mA
- Type: A (AC + pulsating DC)
- Time Delay: Yes – Selective (S-type)
- Voltage: 230/400V AC, 50Hz
- Short Circuit Rating: 6kA
- Mechanical Durability: 4000 cycles
- Electrical Durability: 2000 cycles
- Ingress Protection: IP20 (BS EN 60529)
- Temperature Range: -25°C to +40°C
- Recommended Torque: 2.5Nm
- Conformity: BS EN 61008-1
🔍 Variant Dimensions:
- WARTD463-100: 71.5 × 82 × 70 mm
- WARTD480-100: 71.5 × 82 × 70 mm
- WARTD4100-100: 71.5 × 82 × 70 mm
These time-delayed RCDs must be installed by a qualified electrician and are typically positioned upstream in split-load or cascaded RCD configurations. Correct installation helps achieve discrimination between circuits, preventing full-board disconnection on minor faults.
- Ensure compatibility with downstream RCD ratings (typically 30mA)
- Use correct tightening torque on terminals (2.5Nm recommended)
- Install in a ventilated enclosure to maintain IP20 classification
- Match pole count and current rating to system design
