Technical Manual WIC1
Woodward
DOK-TD-WIC1E, Rev. L
37
5.8.2 Calculation formula for IMT characteristics
Normal Inverse:
𝑡 =
0.14
(
𝐼
𝐼
𝑆
× 𝐼
>
)
0.02
− 1
∙ 𝑎[𝑠]
Very Inverse:
𝑡 =
13.5
(
𝐼
𝐼
𝑆
× 𝐼
>
) − 1
∙ 𝑎[𝑠]
Extremely Inverse:
𝑡 =
80
(
𝐼
𝐼
𝑆
× 𝐼
>
)
2
− 1
∙ 𝑎[𝑠]
Long time inverse:
𝑡 =
120
(
𝐼
𝐼
𝑆
× 𝐼 >) − 1
∙ 𝑎[𝑠]
RI-Inverse Time:
𝑡 =
1
0.339 −
0.236
(
𝐼
𝐼
𝑆
× 𝐼
>
)
∙ 𝑎[𝑠]
HV-Fuse:
𝑡 = 10
(𝑙𝑜𝑔(2∙
𝐼
𝐼
𝑆
×𝐼
>
)∙(−3.832)+3.66)
∙
𝑎
0.1
[𝑠]
FR-Fuse
𝐼
𝐼
𝑆
× 𝐼
>
= 1 − 2 → 𝑡 = 10
(𝑙𝑜𝑔(
𝐼
𝐼
𝑆
×𝐼
>
)∙(−7.16)+3.0)
∙ (
𝑎
0.1
) (𝑠)
𝐼
𝐼
𝑆
× 𝐼
>
= 1 − 2.66 → 𝑡 = 10
(𝑙𝑜𝑔(
𝐼
𝐼
𝑆
×𝐼
>
)∙(−5.4)+2.47)
∙ (
𝑎
0.1
) (𝑠)
𝐼
𝐼
𝑆
× 𝐼
>
> 2.66 → 𝑡 = 10
(𝑙𝑜𝑔(
𝐼
𝐼
𝑆
×𝐼
>
)∙(−4.24)+1.98)
∙ (
𝑎
0.1
) (𝑠)
