Mitsubishi Electronics QD75D, QD75P user manual BIN Binary, Full speed Speed Bias speed

APPENDICES

BCD (Binary Coded Decimal)

1)This is the abbreviation for "binary coded decimal", more accurately called a BCD code. Computers, PLCs, etc., use binary numbers made up of 1 (ON) and 0 (OFF). Because this is difficult for humans to understand, decimal digits are expressed by a pattern of binary digits. Many of the digital switches and digital displays used by humans use a BCD code. The significance of the bits is shown in the drawing below. Numbers from 0 to 9,999 can be handled by 16 bits, and numbers from 0 to 99,999,999 can be handled by 32 bits.

4000+1000+800+40+20+10+2 = 5.872

B15 B14 B13 B12 B11 B10						B9	B8	B7	B6	B5	B4	B3	B2	B1	B0
0	1	0	1	1	0	0	0	0	1	1	1	0	0	1	0	5.872
8000	4000	2000	1000	800	400	200	100	80	40	20	10	8	4	2	1

2)BCD commands are commands in which a binary number (BIN) is converted to a binary coded decimal (BCD).

They are used to output data from the PLC and display it on the digital display.

The following drawing shows a 16-bit example.

MELSEC-Q

BIN (Binary)

1) A binary number, more accurately called a binary code.

All values are expressed as a binary number in which 1 turns the PLC, etc., electricity ON, and 0 turns it OFF. The significance of the bits is shown in the drawing below. In the MELSEC PLC, the highest order bit (B15) is used to indicate handling as a positive No. (0), or negative No. (1), so the 15 bits from B0 to B14 are valid.

128+32+4+2+1=167

B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

0	0	0	0	0	0	0	0		1	0	1	0		0	1	1	1	167
215 214 213 212 211 210 29							28	27		26	25	24	23		22	21	20
Positive/ negative	16384=	8192=	4096=	2048=	1024=	512=	256=	128=		64=	32=	16=	8=		4=	2=	1=

2) BIN commands are commands in which a binary coded decimal (BCD) is converted to a binary number (BIN).

They are used to input the data shown on the digital switch to the PLC.

The following drawing shows a 16-bit example.

BIN code

167 Positive/

BCD code

167

0 negative

0 8000

0	0	0
16384	8192	4096
0	0	0
4000	2000	1000

0	0	0	0
2048	1024	512	256
0	0	0	1
800	400	200	100

1	0	1	0
128	64	32	16
0	1	1	0
80	40	20	10

0	1	1	1
8 4 2 1
0	1	1	1
8	4	2	1

BCD code		0
167		8000
BIN code		0
167	Positive/ negative

0	0	0
4000	2000	1000
0	0	0
16384	8192	4096

0	0	0	1
800	400	200	100
0	0	0	0
2048	1024	512	256

0	1	1	0
80	40	20	10
	0	1	0
1
128	64	32	16

0	1	1	1
8	4	2	1
	1	1	1
0
8 4		2	1

BIAS SPEED AT START

A large amount of torque is required when the machine starts moving, but the torque may be unstable at speed 0 with stepping motors.

Therefore, movement can be smoothly carried out by starting the movement at a given speed from the beginning. The bias speed at start is the speed set at that start.

Full speed

Speed 0

Bias speed

Appendix - 71