|
| DSH 791
% h# h1 m1 I( g* b
) k: ~8 b" ^8 b) R# v | TRFs – Values to be reported, |/ C' o% w/ J6 O3 E1 C3 \: l; V
| General
& A! c' v) F. [! {0 D- E6 y | All IEC standards
& h3 B) r. ^- G- q | ! V e. D: s* m" B
Standard(s):
I; r4 l8 t; ]' o+ U5 @* FAll IEC standards4 X& g8 z! ^( T) g
Subclause(s):; H6 ]! `* L p, E! c% b
General
0 I4 P0 _- U0 L$ i& Y/ TNo. Year: @) O: J0 r# y; j: f w( B
DSH5 V# C C! Q: W3 x+ u+ E
0791 2010
; a: Z( \- S8 Y6 uCategory: VARIOUS Developed by: WG4
# J5 |- [( B0 BSubject:1 k( U! C8 E k2 \
TRFs – Values to be reported6 _2 {/ H7 k" }) ]
Key words:$ s0 D* I2 ^" Q, _+ g
- TRFs
- x" \: _" Y$ U& C( T- Required minimum value1 p- B/ v' F4 J
- OD-CB2020 Ed. 1.7 § 4.6.1( i5 u' c+ E, G& a- G
Approved at the 48th CTL) N3 N. i- ]8 h% V) W" \
Plenary Meeting, in 20119 E% s' t4 J7 ?9 [
Question:
; O* C8 l2 x! \Based on OD-CB2020-Ed.1.7 Sub-clause 4.6.1., it is not allowed to use statements such as “OK”, “meets8 W6 s: V$ @/ u r B
the standard”, “more than”, “less than”, or similar instead of the measured value, unless otherwise
- {' L0 y* l9 V; Especified by CTL.& G& X- X9 h4 y
In certain cases the required minimum value is exceeded by a great margin.( b- o1 o* g" k% E0 B* q
Decision:8 X9 ?) @' {8 h
In case that the measured minimum or maximum value is exceeding or is below the limit value for, S$ I! e, M2 i, U6 E
more than 30%, the value given in the TRF should be >[minimum required value + 30%] or should
+ y8 X+ K; u6 k0 ?. w+ o; Dbe < [maximum required value - 30%]. The accuracy of the used instruments is in line with CTL# k9 {# D7 i# C7 B. A7 W& n# ?
DSH 251B or better.
' O( e6 W+ o: w k6 d' SFor example measurement of insulation resistance:
" O! x& d2 ~* z+ m· required 5 M;
, K, f' W3 T* M8 l& L! A( y· measurement range of test equipment 0 … 10 M;
) i4 w, N, F8 M' l3 x% u& S· the measurement instrument shows full-scale deflexion.
- z. c( A7 @( d7 {) z& jThe value given in the TRF should be > 6.5 M.9 r$ k! V5 x% O7 }
For example measurement of creepage distance:
( z" p$ `# M* e- The required creepage distance is 3.0 mm.;' N. j# j9 q$ X) H# ^ P# F
- The real distance is exceeding 4 mm.;
3 C! r% i" S3 ^The value given in the TRF should be > 4 mm.3 p, w0 H( N- D1 Q% g1 q
For example measurement of leakage current:
- S1 q! v. P! m( K; Y; _- The current limit is 0.5 mA;
. T2 f" Q( C, U% e- The real current is below 0.35 mA;1 D7 H' B" h1 _7 Y0 F
The value given in the TRF should be < 0.35 mA.9 k6 n6 Z7 j1 n5 Z+ _& L
The following two situations are allowed:6 d/ E1 J, ?4 m1 j7 o! A
1 – The meter reading is less than the smallest measurable graduation on a meter scale. For
) K5 ]5 s1 f- M" M- Qexample, touch current measured was less that 0.1 mA.6 M! j5 P7 `7 H
2 – In checking creepage and clearance distances with a probe the same dimension as the& {( ^7 A5 }; J5 r @
requirements. For example, creepage and clearance distances were greater than 0.8 mm.
9 t- p3 O6 y1 F; k5 G
* d% D. F- _& n$ w. @* p$ a( H7 [: Y2 Z5 x* C" A/ G
|
本帖子中包含更多资源
您需要 登录 才可以下载或查看,没有帐号?注册安规
x
|