Delta Electronics VFD-M manual Application Note

Chapter 4 Parameters

Application Note:

PLC program execution will be interrupted when values for JOG parameters 15 and 16 are changed.

Pr.79 PLC Forward/Reverse Motion

Settings 00 to 127Factory Setting: 00

This parameter determines the direction of motion for the multi-speed Pr.17 to Pr.23 and Master Frequency. The original direction of Master Frequency will become invalid.

Note: A 7-bit binary number is used to program the forward/reverse motion for each of the 8 speed

steps (including Master Frequency). The binary notation for the 7-bit number must be translated into decimal notation and then entered in Pr.79.

Weights								0=Forward
								1=Reverse
Bit		7	6	5	4	3	2
								1
								Direction of 1st speed for Pr.17
								Direction of 2nd speed for Pr.18
								Direction of 3rd speed for Pr.19
								Direction of 4th speed for Pr.20
								Direction of 5th speed for Pr.21
								Direction of 6th speed for Pr.22
								Direction of 7th speed for Pr.23
Example:
Weights								0=Forward
								1=Reverse
Bit	7	6	5	4	3	2	1
Direction	0	1	0	0	0	1	0
								Forward motion of Pr.17 multi-speed1
								Reverse motion of Pr.18 multi-speed2
								Forward motion of Pr.19 multi-speed3
								Forward motion of Pr.20 multi-speed4
								Forward motion of Pr.21 multi-speed5
								Reverse motion of Pr.22 multi-speed6
								Forward motion of Pr.23 multi-speed7

The setting value=bit7 x 26+bit6 x 25+bit5 x 24+bit4 x 23+bit3 x 22+bit2 x 21+bit1 x 20

=0 x 26+1 x 25+0 x 24+0 x 23+0 x 22+1 x 21+0 x 20

=0+32+0+0+0+2+0+0

=34

Revision May 2008, ME14, SW V3.04 4-57