SAILMON SYSTEM LOAD CELL BOX MANUAL Sailmon LoadCellBox Manual V1.0 Page 1
Sailmon LoadCellBox Manual V1.0 Page 2
CONTENTS 1. Product Description...4 2. Technical Specifications...5 3. Installation...6 4 wire load cells...7 6 wire load cells...7 Power Supply...8 Calibration Process...9 5. Troubleshooting...11 Sailmon LoadCellBox Manual V1.0 Page 3
1. Product Description The Sailmon Load Cell Box offers connection of load cells to the Sailmon system. It can be used to interface all common 4-wire or 6-wire load cells. Calibration is done with the Sailmon Software Tool. For over-voltage and electrostatic discharge protection the Load Cell Box is galvanically isolated. It will measure tension or pressure with an update rate of 10Hz, allowing monitoring and logging rig tension. With the Sailmon System, the actual force can be displayed in N (Newton), kg, or % of nominal rig load. It is housed in a very small waterproof case and is rated IP65. Sailmon LoadCellBox Manual V1.0 Page 4
2. Technical Specifications Update rate: 10Hz 5m NMEA2000 drop cable (pre-installed) Accuracy: 1% over temperature Maximum input voltage: ±39mV Dimensions (H x W x D): 98mm x 82mm x 33mm Weight: 160g (Cable: 240g) Protection: IP65 Ambient Temperature Range: 0 C to 50 C, 32 F to 122 F Power Supply: NMEA2000 compatible, 9-16V Galvanic isolation of load cell NMEA2000 PGNs Supplied: 64221 (0x0FADD) Sailmon proprietary Sailmon LoadCellBox Manual V1.0 Page 5
3. Installation Installation of the Load Cell Box is a straightforward process. Choose a dry and protected place for the Load Cell Box. The Load Cell Box is designed to be installed inside the hull. The preferred installation location is as close to the sensor as possible. This will keep the sensitive wires between the sensor and the Load Cell Box short. Please note that one fine thing about NMEA2000 is that you do not have to feed analog wires across the boat, so keep sensor wires short and distribute your signals over the NMEA2000 bus. See the Sailmon MM104 Installation and User guide for further information on the NMEA2000 connection. As you have chosen a proper installation location, you have to feed the load cell sensor cable into the left feedthrough of the Load Cell Box and connect the wires according the color scheme printed on the circuit board. NEVER CONNECT ANY OTHER SIGNALS THAN A PASSIVE LOAD CELL SENSOR TO THE CONNECTION TERMINALS. LOAD CELL BOX DAMAGE MIGHT BE THE RESULT. NO PREAMPLIFIER MUST BE CONNECTED TO THE LOAD CELL. Sailmon LoadCellBox Manual V1.0 Page 6
4 WIRE LOAD CELLS Most load cells have a 4 wire connection, where 2 wires are used for the supply of the internal strain gauges, while the other 2 wires provide the measurement signal. The proper connection for 4 wire load cells is as follows: For 4 wire load cells, both jumpers on the back side of the connector terminal must be populated like described in the picture above. CABLE SHIELD CONNECTION IS VERY IMPORTANT, BAD SENSOR PERFORMANCE WILL OCCURE IF LEFT UNCONNECTED. THE CABLE SHIELD MUST BE CONNECTED TO THE SUPPLY- TERMINAL OF THE LOAD CELL BOX AND THE LOAD CELL SENSOR CASE 6 WIRE LOAD CELLS High accuracy load cells have a 6 wire connection, where 2 wires are used for the supply of the internal strain gauges, 2 wires for Supply Feedback and the remaining 2 wires provide the measurement signal. The proper connection for 6 wire load cells is as follows: Sailmon LoadCellBox Manual V1.0 Page 7
For 6 wire load cells, both jumpers on the back side of the connector terminal must be open! CABLE SHIELD CONNECTION IS VERY IMPORTANT, BAD SENSOR PERFORMANCE WILL OCCURE IF LEFT UNCONNECTED. THE CABLE SHIELD MUST BE CONNECTED TO THE SUPPLY- TERMINAL OF THE LOAD CELL BOX AND THE LOAD CELL SENSOR CASE POWER SUPPLY The Load Cell Box is powered from NMEA2000, so no extra power supply is necessary. Make sure your NMEA2000 network is installed according the NMEA2000 standards, including a proper power supply in the range of 9-16V and termination resistors at both ends of the bus. Use a DC/DC converter if you want to power your bus from a 24V service battery voltage. As soon power is applied to the Load Cell Box (over the NMEA2000 interface), the circuits are operating. The blue status led on the front will be on if both power supply and NMEA2000 network are ok. Status LED CHECK THE NMEA2000 POWER AND NETWORK TERMINATION RESISTORS IF THE BLUE LED DOES NOT LIGHT UP! In case all connections are ok, the Load Cell Box will start to send load cell data over NMEA2000 network with a measurement rate of 10Hz. Sailmon LoadCellBox Manual V1.0 Page 8
4. Calibration Calibration of all Load Cell Boxes is done with the Sailmon Config Tool. Open the Sailmon Tool Software and enter the Config Tool. Choose Calibration->Load Cells: Sailmon can connect up to 16 load cells. Choose the respective load cell and select the respective Load Cell Box in the Sensor field. The parameters Load Cell Sensitivity and Load Cell Full-scale must be set according the load cell manufacturers data sheet. These values gives is different for every load cell type. You can enter a Name for this Load Cell in the Description Text field; this Text will appear on the Sailmon monitors. Rated Load is the load the respective part of the rig is rated for. This value is used for a percentage display of the load, meaning that if the load cell measures the value in the Rated Load field, the Monitor will show 100% CALIBRATION PROCESS POWER ON THE LOAD CELL BOX WITH THE LOAD CELL CONNECTED AND WAIT FOR AT LEAST 60 MINUTES BEFORE PERFOMING A ZERO CALIBRATION! Sailmon LoadCellBox Manual V1.0 Page 9
Enter the values for Sensitivity and Full-scale according the load cell manufacturers data sheet. With the load cell mounted correctly and the respective part of the rig completely without tension, press the Zero button. This will set the value to zero and calibrates the load cell. Try to bring tension to the rig now to see if the load cell value is correct. Sailmon LoadCellBox Manual V1.0 Page 10
5. Troubleshooting Problem: The blue status LED does not light up. Solution: Check the NMEA2000 power supply and the termination resistors of the NMEA2000 bus. Problem: The Sailmon system shows very high values. Solution: Check the load cell box connection and the correct jumper placement. Problem: The Sailmon System shows the correct value, but the value is negative. Solution: Exchange the Signal+ and Signal- wires on the terminal connector. Problem: After a software update, my Load Cell Box does not work anymore. Solution: Contact the Sailmon Support in this case. Sailmon LoadCellBox Manual V1.0 Page 11