Option boards
Collect the right data with our option boards
Option boards to customize your data logger
Option boards can be used to add additional inputs/features to an ML-417 data logger or to perform signal conditioning. You can mechanically stack up to 3 option boards, but only one board per category ID (CID). Some boards come with a switch to choose a different CID, so you can stack multiple similar boards.
Converter(OC) or Power (OP) boards don’t have CID’s and you can stack as many OC/OP-boards as mechanical feasible. OC-boards don’t make use of the internal control bus, but are wired to existing inputs/outputs/ports.

Option board category
CID
0x48 & 0x49
SKU, Description
ML-OI-AD-80MV, Dual channel 16-bit differential input.
a/o to connect pyranometers or load-cells
Ranges
- ±80mV
- ±40mV
- ±20mV
- ±10mV
Terminals
1. In 1 (+)
2. In 1 (-)
3. In 2 (+)
4. In 2 (-)
5. Excitation (5V @80mA)
6. Ground
7. CID selector
CID
0x48 & 0x49
SKU, Description
ML-OI-AD-2000MV, Dual channel 16-bit differential input Dual channel 16-bit differential input. a/o to connect thermistors or pH-probes
Ranges
- ±2000mV
- ±1000mV
- ±500mV
- ±250mV
Terminals
1. In 1 (+)
2. In 1 (-)
3. In 2 (+)
4. In 2 (-)
5. Excitation (5V @80mA)
6. Ground
7. CID selector
CID
0x48 & 0x49
SKU, Description
ML-OI-AD-10V, Quad channel 16-bit single ended input
Ranges
- ±10V
- ±5V
- ±2.5V
- ±1.25V
Terminals
1. Input 1
2. Input 2
3. Input 3
4. Input 4
5. Excitation (12V)
6. Ground
7. CID selector
CID
0x48 & 0x49
SKU, Description
ML-OI-AD-20MA, Quad channel 16-bit single ended input
Ranges
- ±20mA
Terminals
1. Input 1
2. Input 2
3. Input 3
4. Input 4
5. Excitation (12V)
6. Ground
7. CID selector
CID
0x48 & 0x49
SKU, Description
ML-OI-AD-PT1000, Dual channel 2 or 3-wire PT1000 input
Ranges
- -40…+85°C (±1.5°C)
- -20…+40°C (±1°C)
- On user calibration:
- -40…+85°C (±0.5°C)
Terminals
1. In 1(+)
2. In 1(-)
3. In 1(-)
4. In 2(+)
5. In 2(-)
6. In 2(-)
7. Wire selector
8. CID selector
CID
0x46
&
0x47
SKU, Description
ML-OI-AX-DI, to add four more digital inputs
a/o to connect pyranometers or load-cells
Ranges
States: 0/1
Max counter: 16777216
Max input voltage: 5V
Max frequency: 500Hz
Terminals
1. Input 1
2. Input 2
3. Input 3
4. Input 4
5. Ground
6. Backup batt.
7. CID selector
CID
0x46
&
0x47
SKU, Description
ML-OI-AX-DS18B20, to connect up to four 1-Wire digital thermometers.
Supported chips:
DS1820, DS18B20, DS18S20, DS1822, DS1920
Terminals
1. Input 1
2. Input 2
3. Input 3
4. Input 4
5. Excitation (3.6V)
6. Ground
7. CID selector
CID
0x46
&
0x47
SKU, Description
ML-OI-AX-HART, Octo channel HART inputdatalogger HART inputs Supports multi-drop topology to connect multiple sensors devided over max 8 input channels.
Terminals
1. Loop (+)
2. Loop (-)
3. Excitation (12V)
4. CID selector
CID
0x46
&
0x47
SKU, Description
ML-OI-AX-RH, to connect an external I2C based humidity sensorI2C RH sensor input. Supported chips: AM2315 (AOSONG) ChipCap2 (Amphenol/Telaire T9602-D-3) SHT3x (Sensirion).
Note: We recommend a cable length of max 0.5m.
Terminals
1. SCL
2. SDA
3. Excitation (3.6V)
4. Ground
5. CID selector
CID
0x76
SKU, Description
ML-OI-BARO, Atmospheric pressure & temperature sensor a/o to compensate readings of level sensors
Ranges
- 300…1200hPa (±2hPa)
- -30…+70°C (±1°C)
Terminals
CID
0x4C
SKU, Description
ML-OI-COM-UART, Serial sensor input (UART)UART to connect sensors with TTL UART port
Ranges
- 300…230k4 bps
- Tx (0…3.3V)
- Rx (0…5V)
Terminals
1. Excitation (3.3V)
2. Transmit
3. Receive
4. Ground
CID
0x4C
SKU, Description
ML-OI-COM-RS232, Serial sensor input (RS232) a/o to connect an NMEA-0183 transponder
Ranges
- 300…230k4 bps
Terminals
1. Excitation (12V)
2. Transmit
3. Receive
4. Ground
CID
0x4C
SKU, Description
ML-OI-COM-RS485, Serial sensor input (RS485) a/o to connect a MODBUS/RTU sensor
Ranges
- 300…230k4 bps
Terminals
1. Excitation (12V)
2. RS485 A+
3. RS485 B-
4. Ground
CID
0x4C
SKU, Description
ML-OI-COM-SDI12, SDI-12 sensor input
Terminals
1. Excitation (12V)
2. Ground
3. Data
CID
0x4D
SKU, Description
ML-OA-RS232, RS232 Auxiliary board. To add a secondary accessory to an ML-417ADS (e.g. to add a second camera)
Ranges
- Off/On (0/3.6V)
- 300…230k4 bps
Terminals
1. Control output (0/3.6V)
2. Transmit
3. Receive
4. Ground
CID
0x4D
SKU, Description
ML-OA-WIFI, WiFi Auxiliary boardWiFi interface To transfer log files by WiFi (TCP, MQTT & HTTP)
Ranges
- <400m
- +19dBm transmit power
- -96dBm sensitivity
- IEEE 802.11b/n/g
CID
0x50
&
0x51
SKU, Description
ML-OO-MODBUS, MODBUS/RTU auxiliary output boardMODBUS Slave To share sensor readings with your local SCADA system.
Ranges
- 32 floating-point values
- 4800…38k4 bps
Terminals
1. RS485 A+
2. RS485 B-
3. Ground
4. CID selector
CID
0x50
&
0x51
SKU, Description
ML-OO-SW, digital output boardGalvanic isolated switches To add three galvanic isolated switches with potential free contacts
Ranges
- ±100V
- ±200mA
Terminals
1. Contact 1a
2. Contact 1b
3. Contact 2a
4. Contact 2b
5. Contact 3a
6. Contact 3b
7. CID selector
CID
n/a
SKU, Description
ML-OC-W2P, Waveform to digital pulse converter. Converts a Sine form to a digital pulse to connect flow or anemo-meters with a passive coil output.
Ranges
- 0…10kHz
- 60mV…24V input
- Off/On (0.1/3.6V) output
Terminals
1. Coil in (+)
2. Coil in (-)
3. Pulse out
CID
0x50
&
0x51
SKU, Description
ML-OP-524, additional power for sensors or standalone power supply. Power switches “on” in parallel with the standard data logger sensor power, from an external control signal or continuously.
Ranges
- 5V@300mA, 12V@200mA
- or 24V@100mA
- Off/On: 0/3…24V
- 3.6V (from batteries)
Terminals
1&2, Power output
3&4, Ground
5. Control input
6. 3.6V supply
7. Volt selector
8. Control mode
CID
0x4A
Ranges
- <160m
- +4dBm transmit power
- -92dBm sensitivity
Discover the possibilities
Want to know more about what YDOC can do to help you with your quest for the right data logger? Do not hesitate to get in contact.