An unofficial summary of facts (addresses, types, units, scaling) from the maker's manual. Not affiliated with the maker; values can differ by firmware or model. Always check the device manual before writing (run commands, settings).
Default communication
| Protocol | Modbus RTU |
|---|---|
| Baud (factory) | 9600 bps — options: 1200, 2400, 4800, 9600, 19200, 38400 |
| Data · parity · stop | 8 · None · 2 |
| Slave ID (factory) | 1 (1~99) |
| Manual address style | Wire address as is (0-based) |
- Defaults from comm manual factory-default table (printed p.31 = PDF p.32): addr 01, 9600, NONE, stop 2, wait 5 ms. 8 data bits and speeds from product manual TCD220015AI p.3.
- Manual writes «300001(0000)»: 1-based reference + hex comm address; first entries are (0000), so the parenthesized value is the 0-based wire address (printed pp.21-23). Frame examples show layout only.
- Broadcast is not supported (comm manual, PDF p.6).
Registers (26)
«Wire» is the 0-based address in the request frame (PortDock's «0-based» notation). Value = raw × scale. Table: HR holding register, IR input register, CO coil, DI discrete input. Function codes in hex.
| Manual | Wire | Table | Name | Type | Unit · scale | R/W | FC | Details |
|---|---|---|---|---|---|---|---|---|
| 300001(0000) | 0 (0x0000) | IR | Measured value | S16 | R | 04 | Integer without decimal point — position in 300002(0001). STND shows -5..110 %, SCAL -1999..9999. 30000 = HHHH (STND over) · -30000 = LLLL (STND under) · 30001 = d-HH (SCAL over) · -30001 = d-LL (SCAL under) · 30002 = F-HH (FREQ over) printed p.21 Table 2.1.1 (PDF p.22) | |
| 300002(0001) | 1 (0x0001) | IR | Decimal point / display mode | U16 | R | 04 | High byte = mode (0 STND, 1 SCAL, 2 FREQ), low byte = decimal places. 0 = STND 0 · 1 = STND 0.0 · 2 = STND 0.00 · 3 = STND 0.000 · 256 = SCAL 0 (0x0100) · 257 = SCAL 0.0 (0x0101) · 258 = SCAL 0.00 (0x0102) · 259 = SCAL 0.000 (0x0103) · 512 = FREQ 0 (0x0200) · 513 = FREQ 0.0 (0x0201) · 514 = FREQ 0.00 (0x0202) · 515 = FREQ 0.000 (0x0203) printed p.21 Table 2.1.1 | |
| 300003(0002) | 2 (0x0002) | IR | HI peak value | S16 | R | 04 | Max of input. Decimal per 300002. printed p.21 Table 2.1.1 | |
| 300004(0003) | 3 (0x0003) | IR | LO peak value | S16 | R | 04 | Min of input. Decimal per 300002. printed p.21 Table 2.1.1 | |
| 300005(0004) | 4 (0x0004) | IR | OUT status (HI, GO, LO) | U16 | R | 04 | HI/GO/LO states (0 OFF/1 ON). Bit positions not given in manual — use discrete inputs 100001-100003 instead. printed p.21 Table 2.1.1 | |
| 100001(0000) | 0 (0x0000) | DI | OUT status LO | BIT | R | 02 | 0 = OFF · 1 = ON printed p.22 Table 2.1.2 | |
| 100002(0001) | 1 (0x0001) | DI | OUT status GO | BIT | R | 02 | 0 = OFF · 1 = ON printed p.22 Table 2.1.2 | |
| 100003(0002) | 2 (0x0002) | DI | OUT status HI | BIT | R | 02 | 0 = OFF · 1 = ON printed p.22 Table 2.1.2 | |
| 400001(0000) | 0 (0x0000) | HR | High preset (H.SET) | S16 | R/W | 03·06·10 | OUT HIGH set value. Decimal per display setting (300002). printed p.22 Table 2.1.3.1 | |
| 400002(0001) | 1 (0x0001) | HR | Low preset (L.SET) | S16 | R/W | 03·06·10 | OUT LOW set value. Decimal per display setting (300002). printed p.22 Table 2.1.3.1 | |
| 400003(0002) | 2 (0x0002) | HR | High peak (H.PEK) | S16 | R/W | 03·06·10 | Max of input, default 0. printed p.22 Table 2.1.3.1 | |
| 400004(0003) | 3 (0x0003) | HR | Low peak (L.PEK) | S16 | R/W | 03·06·10 | Min of input, default 0. printed p.22 Table 2.1.3.1 | |
| 400101(0064) | 100 (0x0064) | HR | Input range (IN-R) | U16 | R/W | 03·06·10 | Code table not given (refers to input specifications). printed p.22 Table 2.1.3.2 | |
| 400102(0065) | 101 (0x0065) | HR | Display mode (DISP) | U16 | R/W | 03·06·10 | 0 = STND · 1 = SCAL · 2 = FREQ printed p.22 Table 2.1.3.2 | |
| 400103(0066) | 102 (0x0066) | HR | Decimal point (DOT) | U16 | R/W | 03·06·10 | 0-3; manual shows values only as 7-segment glyphs, so positions are not stated here. printed p.22 Table 2.1.3.2 | |
| 400104(0067) | 103 (0x0067) | HR | High scale | S16 | R/W | 03·06·10 | Raw range; changes with decimal point. Range -1999 ~ 9999 printed p.22 Table 2.1.3.2 | |
| 400105(0068) | 104 (0x0068) | HR | Low scale | S16 | R/W | 03·06·10 | Raw range; changes with decimal point. Range -1999 ~ 9999 printed p.22 Table 2.1.3.2 | |
| 400106(0069) | 105 (0x0069) | HR | Input type (IN-T, AC models) | U16 | R/W | 03·06·10 | 0 = T.RMS · 1 = A.RMS · 2 = AVG printed p.22 Table 2.1.3.2 | |
| 400206(00CD) | 205 (0x00CD) | HR | Front zero key | U16 | R/W | 03·06·10 | 0 = NO · 1 = YES printed p.22 Table 2.1.3.3 | |
| 400207(00CE) | 206 (0x00CE) | HR | Event input function | U16 | R/W | 03·06·10 | 0 = HOLD · 1 = ZERO printed p.22 Table 2.1.3.3 | |
| 400210(00D1) | 209 (0x00D1) | HR | Comm address | U16 | R/W | 03·06·10 | Range 1 ~ 99 printed p.23 Table 2.1.3.3 | |
| 400211(00D2) | 210 (0x00D2) | HR | Comm speed | U16 | R/W | 03·06·10 | 0 = 1200 bps · 1 = 2400 bps · 2 = 4800 bps · 3 = 9600 bps · 4 = 19200 bps · 5 = 38400 bps printed p.23 Table 2.1.3.3 | |
| 400212(00D3) | 211 (0x00D3) | HR | Parity | U16 | R/W | 03·06·10 | 0 = NONE · 1 = EVEN · 2 = ODD printed p.23 Table 2.1.3.3 | |
| 400213(00D4) | 212 (0x00D4) | HR | Stop bit | U16 | R/W | 03·06·10 | 0 = 1 bit · 1 = 2 bits printed p.23 Table 2.1.3.3 | |
| 400214(00D5) | 213 (0x00D5) | HR | Response waiting time | U16 | ms | R/W | 03·06·10 | Range 5 ~ 99 ms printed p.23 Table 2.1.3.3 |
| 400215(00D6) | 214 (0x00D6) | HR | Lock (LOC) | U16 | R/W | 03·06·10 | 0 = OFF · 1 = LOC1 · 2 = LOC2 · 3 = LOC3 printed p.23 Table 2.1.3.3 |
Notes
- RS485 only on output code 8 (NPN + RS485) and 9 (PNP + RS485) (product manual p.2). □ = power code (1: 12-24 VDC, 4: 100-240 VAC).
- MT4Y (section 2.2) uses different holding addresses (e.g. comm address at 400213(00D4)); this file is MT4W only.
- Page numbers: printed page = PDF page - 1.
Read it with PortDock
- Install the free PortDock Modbus Master and connect with the device's settings.
- On the table toolbar, «Device profile…» → pick this device → «Load». Polling tables, names, types and the Slave ID are filled in (optionally the serial settings too).
- Names carry the unit and scale (e.g. «×0.01 Hz»). Values on screen are raw — multiply by the scale.
- To test your program without the device, PortDock Modbus Slave's «Emulate device…» serves the same map with example values.
Download JSON
- autonics/mt4w.json (GitHub raw) · copy on this site · history
- schema.json — format (JSON Schema). table, address (0-based), type and order match the PortDock CSV.
- License: CC BY 4.0 — please credit «PortDock device register maps» with a link. LICENSE
- Found a mistake? Please open a GitHub issue with the manual page.
Sources
- User Manual for Communication 4-Digit Multi Panel Meters MT Series MCT-MTC1-V1.7-EN — Autonics, MCT-MTC1-V1.7-EN (2024-11-26) · printed pp.21-23 (PDF pp.22-24) mapping table, printed p.31 (PDF p.32) factory defaults · checked 2026-10-19
- 4-Digit Multi Panel Meters MT4W Series PRODUCT MANUAL TCD220015AI — Autonics, MT4W_EN_TCD220015AI_20260629 · p.2 ordering information, p.3 Communication Interface · checked 2026-10-19