Datasheet

71M6541D/F/G and 71M6542F/G Data Sheet
136 Rev 4
5.3.11 CE Calibration Parameters
Table 92 lists the parameters that are typically entered to effect calibration of meter accuracy.
Table 92: CE Calibration Parameters
CE
Address
Name Default Description
0x10
CAL_IA
16384
These constants control the gain of their respective channels. The
nominal value for each parameter is 2
14
= 16384. The gain of each
channel is directly proportional to its CAL parameter. Thus, if the
gain of a channel is 1% slow, CAL should be increased by 1%.
Refer to the 71M6541 Demo Board User’s Manual for the equations
to calculate these calibration parameters.
†
71M6542 only.
0x11
CAL_VA
16384
0x13
CAL_IB
16384
0x14
†
CAL_VB
16384
0x12
PHADJ_A
0
These constants control the CT phase compensation. Compensation
does not occur when PHADJ_X = 0. As PHADJ_X is increased,
more compensation (lag) is introduced. The range is ± 215 – 1. If
it is desired to delay the current by the angle Φ, the equations are:
Φ
⋅−
Φ
⋅
=
TAN
TAN
XPHADJ
0131.
01487.
0
02229.0
2_
20
at 60Hz
Φ⋅
−
Φ
⋅
=
TAN
TAN
XPHADJ
009695
.01241
.0
0155
.0
2_
20
at 50Hz
0x15
PHADJ_B
0
0x12
DLYADJ_A
0
The shunt delay compensation is obtained using the equation
provided below:
( )








+








+








∆+∆=
s
ss
reesrees
f
f
c
b
f
f
ab
f
f
a
XDLYADJ
π
ππ
π
2
sin
2
cos2
2
cos
360
2
21.01_
22
14
degdeg
where:
Aa 2=

1
2
+= Ab

= 2

+ 4
2


+ 2
Where, f is the mains frequency and f
s
is the sampling frequency.
The table below provides the value of A for each current channel:
Channel
Value of A
(decimal)
Eq. 0 or 2
Eq. 1
DLYADJ_A
15811 / 2
14
6811 / 2
14
DLYADJ_B
-1384 / 2
14
-1384 / 2
14
0x15
DLYADJ_B
0