ZES ZIMMER LMG450, Руководство пользователя

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Normal measuring mode LMG450
88
AC component:
Uac Utrms Udc
= − 2 2
Iac Itrms Idc
= − 2 2
peak-peak value:
Upp u t u t
= −
max( ( )) min( ( )) Ipp i t i t
= −
max( ( )) min( ( ))
rectified value:
Urect
T
u t dt
t
T
=
=
∫
1
0
( ) Irect
T
i t dt
t
T
=
=
∫
1
0
( )
crest factor:
Ucf
Upk
Utrms
=
Icf
Ipk
Itrms
=
form factor:
Uff
Utrms
Urect
=
Iff
Itrms
Irect
=
Inrush current:
Iinr i t
=
max( ( ) )
Power
active power:
P
T
u t i t dt
t
T
=
=
∫
1
0
( ) ( )
reactive power
Q S P
= − 2 2
apparent power:
S Utrms Itrms
=
*
power factor:
S
P
PF
= = λ
Behind the power factor might be a ‘i’ or ‘c’ showing, that the load is inductive or capacitive.
This decision is only done under following conditions:
λ
< < < < < <
0 999 1 05 1 2 1 05 1 2 1 . . . . . and Uff and Iff and f kHz
This means, that voltage and current are nearly sinusoidal. In all other cases there is neither ‘i’
nor ‘c’.
Please note: The i/c indication was developed for usual line applications. When the usage of
the channels is very low or you work with very high frequencies you should take care, if the i/c
indication is correct or not.
angle:
i u ui
with
ϕ ϕ ϕ ϕ λ ϕ − = = =
arccos
The sign of the angle is derived from the i/c indication, ‘+’ for an inductive load, ‘-’ for a
capacitive one. Here the current is the reference. This value is only valid at sinusoidal wave
forms! The value can be in the range
±
180°, values outside
±
90° usually indicate negative
active power.