Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971


Gilbert is the CGS system unit of magneto-motive force. The equivalent SI unit is Ampere-turn, and 1 Gilbert = 10/4π or 0.7958 Ampere-turns. When measuring the operate AT of a reed switch using a simply power supply and a coil, it is easy to calculate the operate AT by just noting the operate current and multiplying it with the number of turns in the test coil.

Gilbert_(unit) (Wikipedia)

The gilbert (symbol: Gb) is an obsolete unit used in practical cgs and CGS-EMU systems to measure magnetomotive force. The unit is named for English physicist William Gilbert.


  • 1 Gb = (1/4π) Bi-t

Conversion to the corresponding quantity in the SI, with the unit ampere-turn (A⋅t):

  • 1 Gb ≘ (10/4π) A-turn ≈ 0.7957747 A⋅t
  • 1 A-turn ≘ 4π × 10−1 Gb
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