Danfoss VLT HVAC Drive Metasys N2, Руководство пользователя

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Example 3:
Over-ride analog output, speed (50%)
change command:
Setting:
Device address XX
Char1 command 7
Char1 subcommand 2
Char2 region 03
Char2 object number (NPA) 00
Char8 override value * 4E 00 00 00 override value = 50% speed (IEEE
floating point, format)
Checksum YY
Telegram code:
>XX7203004E000000<CR>
To calculate override value for speed: refer to
Scaling of Bus Reference and Bus Feedback.
Issue an override release command through
the master to the device:
Example 4:
Bus stop, BO over-ride release com-
mand:
Setting:
Device address XX
Char1 command 7
Char1 subcommand 2
Char2 region 04
Char2 object number (NPA) 04 (Start)
Char8 override value * 00 (Not active)
Checksum Y
Telegram code:
>XX72040400YY <CR>
If the preceding commands were issued, the
drive should have accelerated to 50% after
the speed reference was issued. After the
override release, the drive should have stop-
ped.
2.2.2. Scaling of Bus Reference and Feedback
Reference/feedback Scaling Float IEEX hex
20% 20 * 16384/100 3276.8 454C CCCD
50% 50 * 16384/100 8192 4600 0000
100% 100 * 16384/100 16384 4680 0000
200% 200 * 16384/100 32767 46FF FE00
-100% -100 * 16384/100 -16384 C680 0000
-200% -200 * 16384/100 -32768 C700 0000
Table 2.11: Reference/feedback values
The reference/feedback value is the percentage of the range of parameter 3-02 and 3-03. Values
within the ranges 100% to 200% and -200% to -100% applies only to the reference. The Float
representation of the value 200% must be limited to maximum 32767 and minimum -32768.
VLT ® HVAC Drive Metasys N2 2. Instructions
MG.11.G1.02 - VLT ® is a registered Danfoss trademark
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