ZINC OXIDE VARISTOR
ZINC OXIDE VARISTOR SELECTION (ONLY REFERENCE)
Varistor voltage
Varistor voltage should be more than the operating voltage in over-voltage protective circuit The formula is shown as the following:
V1mA+a.v/b.c
a-power Voltage ripple coefficient usually take 1.2
v-DC Voltage (significant value only AC power)
b-Tolerance usually take 0.85
c-Ageing coefficient usually take 0.9
The calibrated Value is 1.5 times of DC voltage, the face value should be
current power.
Withstanding surge current
times of the calibrated value because of the peak voltage in alternating
In general, withstanding surge current is max. Pulse current value which determined by test conditions such as wave-shape, shock times and interval
time etc, the change ratio of Varistor Voltage should be less than ±10% of the initial Value. The shock time is the function of wave - shape, amplitude and
interval time ,when the amplitude decrease to 50% of the initial, it should be increased to 2 times of the initial in order to keep the life longer, the surge
current which is absorbed by the varistor should be less than max. Withstanding surge current.
GENERAL TYPE DIMENSIONS
General type is widely used in surge protection for IC. diode. trial semiconductor, thyristor, consumer, military industry telecommunication measuring &
controlling instrument etc.
(V) Varistor Voltage D Max D ±0.1
18~ 82
05
100~ 470
07 18~ 470
18~ 330
10
360~ 1100
18~ 330
14 360~ 1100
180
18~ 330
360~ 1100
20
1800
7.0 0.6
7.5 0.6
9.0 0.6
13.5 0.8
14.0 0.8
17.0 0.8
17.5 0.8
25.0 0.8
23.0 1.0
24.0 1.0
25.0 1.0
W ±1.0
5.0
5.0
5.0
7.5
7.5
7.5
7.5
15.0
10.0
10.0
15.0
H
T Max
Max
10.0 3.5 H
10.0 6.0
12.0 6.0
16.5 5.4
17.0 8.5
20.0 5.4
20.5 8.5
30.0 12.0 3 min
27.0 5.5
28.0 9.0
30.0 12.0
D
Фd
w
T
LIGHTNING ARRESTER TYPE
Lightning arrester type is ideal for semiconductor, signal relay, telecommunication, calibrating equipment, communication inter-medium station,
distribution board, surge absorption and lightning-protection of all sorts of electric equipment because of the properties, with the Great withstanding surge
current, wide voltage, quick responding speed and low residual voltage etc.
Part No.
Dimensions(mm)
DT
DT
W dH
FNR-25
FNR-32
30
38
12
13
15 1.5
30±1mm
Фd
18 1.5
FNR-40
45
13
20 1.5
w
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