V/m with the same charge. Consequently, cold storms often induce higher electric fields at the
ground but they may not produce lightning.
J.1 Site calibration
The site calibration requires two CS110 electric field meters. One CS110 is the the reference
calibrator and the other CS110 is the device under calibration (DUC). The reference calibrator can
be a CS110 installed on the ground surface facing up or the Transfer Standard installation shown
in Figure J-1 (p. 69). The downward facing Transfer Standard calibrator is easier to use because it
is not affected by rain and dirt whereas the up facing CS110 calibrator is.