PLC Digital Signal · Free Calculator
PLC Status Word and Bit Decoder
Decode a drive status word, alarm word or PLC fault word: enter the value and see every bit that is on, with its weight in decimal and hex.
Bit by bitHex and binaryDrive status word16 and 32 bit
Bits set0, 1, 5, 10, 15
Decimal33827
Hex0x8423
Binary1000 0100 0010 0011
As signed−31709
Bit map
| Bit | State | Weight | Hex |
|---|---|---|---|
| Bit 0 | ON | 1 | 0x1 |
| Bit 1 | ON | 2 | 0x2 |
| Bit 2 | off | 4 | 0x4 |
| Bit 3 | off | 8 | 0x8 |
| Bit 4 | off | 16 | 0x10 |
| Bit 5 | ON | 32 | 0x20 |
| Bit 6 | off | 64 | 0x40 |
| Bit 7 | off | 128 | 0x80 |
| Bit 8 | off | 256 | 0x100 |
| Bit 9 | off | 512 | 0x200 |
| Bit 10 | ON | 1024 | 0x400 |
| Bit 11 | off | 2048 | 0x800 |
| Bit 12 | off | 4096 | 0x1000 |
| Bit 13 | off | 8192 | 0x2000 |
| Bit 14 | off | 16384 | 0x4000 |
| Bit 15 | ON | 32768 | 0x8000 |
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Reading a Status Word
Word value = Σ 2bit for every bit that is on
Bit 0 is the least significant bit
Bit 0 is the least significant bit
Worked example
0x8423 = 33827: bits 0, 1, 5, 10 and 15 are on. On many drives bit 15 of the status word signals a fault or alarm, so check the drive manual for the bit meanings.
Key insight: when a drive or device sends a negative number, it is usually just a 16 bit word with bit 15 set read as a signed integer; the bit pattern is what matters.
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Frequently Asked Questions
How do I find which bits are set in a word?
Convert the value to binary; each 1 is a set bit, counting from bit 0 on the right.
Why is my status word negative?
Bit 15 is set and the PLC reads the word as a signed integer.
What does 0x0001 mean?
Only bit 0 is set.
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