17
capacitance and reducing leakage on the dielectric loss test results.
(1)
Distance between high voltage and low voltage 2mm
⑵
Dry cell capacitance 60±5PF
⑶
Maximum test voltage (power frequency) 2000V
⑷
Dry cell dielectric loss tan δ
＜
1×10-4
⑸
Liquid capacity
about 40ml
⑹
Electrode material
Stainless steel
⑺
Volume
70mm (D) × 120mm (H)
3
、
Loading and taking out the test cell
⑴
Loading the test cell
：
Place the test cell smoothly into the heating furnace of the
instrument, tighten it clockwise to ensure good contact at the bottom, so that there is good
electrical contact and thermal contact. Insert the test cable into test cell until it engages and
connects the test electrode plug, and insert the temperature sensor into the hole of inner
electrode.
⑵
Taking out the test cell
：
Drain the oil in test cell out, turn it counterclockwise, and
remove the test cable and temperature sensor to take out the test cell directly.
Attention
：
Be sure to drain the oil in the test cell clean and then remove it.
4
、
Dismantling and assembling the test cell’s electrode
Loosen the fixed button
④
and carefully withdraw the measuring electrode; Similarly,
Place the measuring electrode and tighten the fixed button.
Attention
：
Inner electrode is very precision components, when you take out and load it,
actions must be slow and steady. Do not collide between the internal and external electrode
in case of damaging the surface and causing the entire test cell scrapped.
5
、装入油样
5
、
Loading oil sample
Fill the filling glass tube (Fig.18-1) with test medium by the rinsed container until it
appears in the deaeration glass tube (Fig.18-2), stationary for 5 minutes, and then start
testing when the oil surface in the filling glass tube is level with the surface in the deaeration
tube sight glass.
6
、
Drain the oil.
The test medium is drained out by pressing the drain oil button; Fill the test cell with
