Reed Switches Protection

Reeds Switches are hermetically sealed contacts actuated by a magnetic field.

The life expectancy of a reed switch refers to a kind of load to be used. Reed Switches of the highest reliability are applied in our level switches, flow switches and their life expectancy can reach above two million operations. However when they are switching lamps, inductive or capacitive loads, this number may decrease.

Switching Power of Reed Contact

It is important to consider that the power specified by an electrical load is often referred to the permanent working state.

Operating Voltage Max. Switching Power Max. Switching Current Peak Current
110Vac 20VA 0.2A 0.5A @20ms
220Vac 20VA 0.1A 0.5A @20ms
5Vdc 2.5W 0.5A 1A @20ms
12Vdc 5W 0.5A 1A @20ms
24Vdc 10W 0.5A 1A @20ms
  • OPERATING VOLTAGE: 110Vac
    • Max. Switching Power: 20VA
    • Max. Switching Current: 0.2A
    • Peak Current: 0.5A @20ms
  • OPERATING VOLTAGE: 220Vac
    • Max. Switching Power: 20VA
    • Max. Switching Current: 0.1A
    • Peak Current: 0.5A @20ms
  • OPERATING VOLTAGE: 5Vdc
    • Max. Switching Power: 2.5W
    • Max. Switching Current: 0.5A
    • Peak Current: 1A @20ms
  • OPERATING VOLTAGE: 12Vdc
    • Max. Switching Power: 5W
    • Max. Switching Current: 0.5A
    • Peak Current: 1A @20ms
  • OPERATING VOLTAGE: 24Vdc
    • Max. Switching Power: 10W
    • Max. Switching Current: 0.5A
    • Peak Current: 1A @20ms

24Vac: NOT recomended

For higher power, use an auxiliary relay or contactor as recommended below (power consumption table).

  • Siemens 3RT1015 Contactor

    Initial: 31.7VA

    Rated: 5.1VA

  • Weg CW07 Mini Contactor

    Initial: 19.3VA

    Rated: 5.5VA

  • Schneider CA2KN Contactor

    Initial: 30VA

    Rated: 4.5VA

Note: Reed Switches have reached over one million operations in tests with mini contactor and snubber filter K8.

PROTECTION PROCEDURES BELOW DESCRIBED CAN IMPROVE THE REED SWITCH PERFORMANCE

• Switching inductive loads

Reed Switch Contactor
2K2 - 2W
0.1µF 400V
Filter K8 mounted in parallel with the coil of an AC contactor, increases the contact life.
Esquema con filtro K8
Reed Switch
BY448
or
1N4007
Filter KD mounted in parallel with the coil of a DC relay, increases the contact life.
Esquema con filtro K8

? Risk of failure (welding of the Reed Switch Contact) due to CAPACITANCE, which can occur depending on the distance and cable used in the connection to the contactor.

• Connecting the sensor to a contactor in long distances, use resistor:

D = 20 ~ 40m 22R 5W Esquema de conexión en largas distancia
This resistor dampens the peak voltage caused by the capacitance of cables and electronic equipment input.

! Important! For distances greater than 40m, use 24Vdc voltage.

• Connecting the sensor to an electronic equipment:

220R 5W Esquema de conexión con aparato electrónico

Example:

  • • Timing relay
  • • Frequency inverter
  • • Etc.

! Important! For installation with relay coupler, use 4K7 10W resistor.