User manual
Reference PTQ-104S Rev2 ♦ Quantum Platform
User Manual IEC 60870-5-104 Server for Quantum
Page 142 of 195 ProSoft Technology, Inc.
February 22, 2013
The following table describes how these points would be stored in the module:
400
Word 10 (Word address 10)
401
Word 12 (Word address 12)
402
Word 18 (Word address 18)
Monitored Measured Normalized points use a data representation defined by the
protocol specification to represent fractional decimal values. The following table
describes the value for each bit as a reciprocal power of two (2), that is two (2)
raised to the power of a negative exponent ( -1 through -15). Bit 15 is the Sign
Bit.
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Value
Hex(h)
Decimal
Sign
4000h
2
-1
2000h
2
-2
1000h
2
-3
800
h
2
-4
400
h
2
-5
200
h
2
-6
100
h
2
-7
80
h
2
-8
40
h
2
-9
20
h
2
-10
10
h
2
-11
8h
2
-12
4h
2
-13
2h
2
-14
1h
2
-15
4000h
0.5
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2000h
0.25
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
1000h
0.125
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
6000h
0.75
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
3210h
0.395751953125
0
0
1
1
0
0
1
0
0
0
0
1
0
0
0
0
Examples:
A value of 4000hex (only Bit 14 set, all others clear) is interpreted as 0.5 decimal
A value of 2000hex (only Bit 13 set, all others clear) is interpreted as 0.25
decimal
A value of 1000hex (only Bit 12 set, all others clear) is interpreted as 0.125
decimal
... and so on until...
A value of 0001hex (Only Bit 0 set, all others clear) is interpreted as
0.000030517578125
Therefore, the actual data values transmitted may be any combination of the
decimal values for any given bit pattern.
M_ME_NC and M_IT_NA
The monitored measured short floating point and monitored integrated total
points occupy two words with double-word addressing.