Specifications

7. Application Instructions
© DELTA ELECTRONICS, INC. ALL RIGHTS RESERVED
7-53
 Control diagram:
SV E MV PV
1/S K
I
K
P
K
D
S
G(s)
++
+
-
-
100 MODRD
S1 S2 n MODBUS data read
Bit device Word device
Device
Operand
X Y M S K H KnX KnY KnM KnS T C D E F
S1
ϨϨ Ϩ
S2
ϨϨ Ϩ
n
ϨϨ
 MODRD is a command for the MODBUS ASCII mode communication.
(Version 3.3 and above contain RTU mode, controlled by M1143).
The Delta VFD series drives have build-in MODBUS communication.
Please refer to the Delta VFD Series Manual for more details.

S1
Communication address: K00000~K00254.

S2
Read out address. If the address setting is illegal, the user will
be informed by an error message. The error code will be saved in
D1130, at the same time, M1141 will turn ON. For example, 4000H is
an illegal address to VFD-S, M1141 will turn ON, D1130=2. Refer to
Delta VFD-S series AC drive manual on fault information.

n
Data length,nЉ6.
 The feedback data from peripherial equipment will be saved in D1070
to D1085. PLC will check the data after SAVE function is complete. If
there is an error, then M1140 will be ON.
 Because the feedback data are all ASCII characters, PLC will convert
the feedback data to value data and store them in D1050 to D1055.
101 MODWR
S1 S2 n MODBUS Data write
Bit device Word device
Device
Operand
X Y M S K H KnX KnY KnM KnS T C D E F
S1
ϨϨ Ϩ
S2
ϨϨ Ϩ
n
ϨϨ
 MODWR is a command for the MODBUS ASCII mode communication.
(Version 3.3 and above contain RTU mode, controlled by M1143).

S1
Communication address: K00000 to K00254.

S2
Write address. If the address setting is illegal, the user will be
informed by an error message. The error code will be saved in D1130,
at the same time, M1141 will ON.

n
Write data.
 The feedback data from perpherial equipment will be saved in D1070
to D1076. PLC will check the data after the SAVE function is complete.
If there is an error, M1140 will be ON.