2 Pole A-Type 100mA Time Delay RCD
The WARTD Series A-Type 100mA Time Delay RCD is designed for upstream fault protection in dual-RCD or discrimination setups. Often referred to as an S-Type RCD, its built-in delay ensures downstream devices trip first, preventing unnecessary loss of power across unaffected circuits. Suitable for both single-phase and 3-phase TN or...
The WARTD Series A-Type 100mA Time Delay RCD is designed for upstream fault protection in dual-RCD or discrimination setups. Often referred to as an S-Type RCD, its built-in delay ensures downstream devices trip first, preventing unnecessary loss of power across unaffected circuits.
Suitable for both single-phase and 3-phase TN or TT systems, this RCD is a proven choice for EV charging infrastructure, solar PV arrays, and industrial distribution boards where selective coordination is essential. Fully compliant with BS EN 61008-1.
- Time delay function – enables upstream discrimination in series RCD setups
- Available sensitivities: 30mA, 100mA, or 300mA
- Rated currents: 63A, 80A, or 100A
- A-Type residual current characteristics – detects AC and pulsating DC leakage
- DIN rail mountable – compact 36mm width
- Compliant with: BS EN 61008-1
Built for scenarios where coordination between devices is critical, this unit provides reliable protection while avoiding unnecessary trips. Always install in line with BS 7671 and your consumer unit design requirements.
What is a 100mA time delay RCD used for?
It’s designed for upstream protection in circuits with multiple RCDs. The delay ensures that only the RCD closest to the fault trips, maintaining supply elsewhere.
Can I use this for EV installations?
Yes - if your setup includes both upstream and final circuit protection, this device helps meet discrimination requirements in EV, solar, or generator installs.
Is this compliant with the 18th Edition regs?
Yes. It complies with BS EN 61008-1 and supports 18th Edition coordination requirements when used appropriately.
- Type: A-Type (S-Type) Time Delay RCD
- Sensitivity: 30 / 100 / 300mA (set internally)
- Poles: 2P
- Current Ratings: 63A, 80A, 100A (selectable)
- Dimensions: 36 x 82 x 70mm
- Rated Operational Voltage: 230/400V, 50Hz
- Short Circuit Rating: 6kA
- Mechanical Endurance: 4000 cycles
- Electrical Endurance: 2000 cycles
- Ingress Protection: IP20 (BS EN 60529)
- Compliance: BS EN 61008-1
- Recommended Torque: 2.5Nm
Time delay RCDs should only be used where discrimination is needed — typically as the upstream device in multi-board or split-load setups. Always confirm placement during design or testing stages.
- Mount directly to DIN rail inside suitable enclosure
- Ensure correct torque is applied to terminals (2.5Nm)
- Time delay should not be used on final circuits without discrimination needs
- Install by a qualified electrician only
