| 摘要 |
FIELD: physics. ^ SUBSTANCE: in the method of measuring resistance of the earthing device of a direct current railway substation, the measuring current is part of the traction current flowing on the earthing device of the direct current railway substation, connected through a drainage apparatus to the negative terminal of the supply; the value of current through the earthing device is determined by dividing voltage across the shunt of the drainage apparatus by resistance of that shunt; the unknown resistance of the earthing device is calculated using the formula: where Rsh is the resistance of the shunt of the drainage apparatus. Ush is the voltage across the shunt of the drainage apparatus, Ue is the voltage between the earthing device and a remote potential electrode carried to "the zero potential point". ^ EFFECT: considerable increase in measurement accuracy by increasing measuring current, reduced labour input and expenses on measuring since there is no need to use a portable generator, an ammeter, a current electrode and coils with long wires. ^ 1 dwg |
