Figure 5-32. Scaling Example For Voltage Mapped Registers - ABB TPU2000 Technical Manual

TPU2000/2000R Modbus/Modbus Plus/ Modbus TCP/IP Automation Guide
Full Scale = 10 MAX VALUE ALLOWABLE ON FPI = 10 * CT ratio.
CT Ratio (Current Calculation) = 100:1 (as per the default screen shown in Figure 8-2)
Source Value Location = 385 [ 16 Bit Value Signed
Calculate the 12 bit scaled reading when the TPU2000R indicates 5A for Ia.
(12 bits -1)
(( 2 * 5A)/(10 * 100)) +(2
Thus Equation 7 illustrates that a current of 5A displayed on the MMI shall indicate a count of 3071 reported to the
SCADA Host when register 40002 is read. The SCADA host shall then interpret it and display it on its host screen
as 5 A.
Perhaps another example shall suffice. The TPU2000/2000R also meters voltages. The next example illustrates
the scaling which occurs for the default registers, 40006, and 40007. Figure 8-8 shows the scale algorithm
application for scaling to an Offset Bipolar 12 bit number.

Figure 5-32. Scaling Example for Voltage Mapped Registers

The values used for this example are:
Full Scale = 500
PT Ratio (Current Calculation) = 100:1
Source Value Location = 513 [neglect the leading 4]
Using Equation 6 the following results when calculating the numeric value reported to the SCADA host when
register 40005, 40006 or 40007 is accessed.
(12 bits -1)
(( 2 * 11884)/(500 * 100)) + (2
1622.562
When the front panel MMI reads 11884 V, a value of 3699 is reported to the SCADA host.
One final example is illustrated for transferring values from different areas in the protective relay to the default
table. Such values as Relay status (located in register 40129 and transferred to 40001), Phase CT ratio (used by
the SCADA host to provide for scale conversion located in Register 40158 and transferred to 40016), PT ratio
(used by the SCADA host to provide for scale conversion in Register 40160 and transferred to 40017), and
system frequency (located in Register 40027).
(12 bits -1)
- 1) = 3071 counts.
TPU2000R
32
Network
Partner Mappable
DPU
STATUS TARGE TS V1.0
A 2000R
NORMAL TIME
FAIL B
INSTANTANE OUS
PICKUP FREQUENCY C
C Registers
RECLOSER OUT NE GATIVE SEQUE NCE
N
SYSTE M RESE T TA RGET RESET
E
Va Voltage Mag. Hi
40265
40266 Va Voltage Mag. Lo
40268
VbVoltage Mag. Hi
40269
VbVoltage Mag. Lo
Vc Voltage Mag. Hi
40271
Vc Voltage Mag. Lo
40272
Value stored in Registers
40005, 40006,and 40007 read by
the SCADA Host.
RTU or Host Reads 4095
RTU or Host Reads 2047
RTU or Host Reads 0
(12 bits -1)
+ 2047 = 3699
Change Register Configuration
400001
.
OFFSET BIPOLAR
.
.
12 bit resolution
400005
0 = (-) Full Scale
400006
(12 bits -1)
400007
2 - 1 = 2047 =
(12 bits)
2 - 1 = 4095 = (+) Full Scale
400032
TPU 2000/2000R Metered Value reported
to the MMI SCREEN
(+) Full Scale = 50000 V = FS * PT
0 Amperes
(-) Full Scale = - 50000 V = FS * PT
32 Bit Value Unsigned
- 1) = 3699.562 counts
0
84