The following is a guide for connecting the Brain (DRV25/DRV40/DRV80) to a BAS using a Modbus RTU protocol. Please review the appropriate Brain Installation and Maintenance guide available at www.armstronginternational.come/brain to familiarize yourself with the product specification and installation before attempting to connect the BAS. Armstrong International IOM-776 Brain ®...
2. Reprogramming can also be done via this port if the laptop has the latest Bootloader software installed. CN2 is the internal network connection for the Brain ® . CN2 also uses RS485, but with the option of running either the BrainScan ® protocol or Modbus RTU protocol. Armstrong International IOM-776 Brain ® Modbus Networking...
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CN7 is a multi-functional port that can be used for a variety of operations: 1. Bootload new valve software (requires a USB to RS485 cable connection and Bootloader PC software - contact Armstrong). 2. Configure and fault find the valve through diagnostic reporting.
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The cable connecting to the BMS should be Cat5 twisted pair and should be in a ‘daisy chain configuration’. Wiring arrangement should be as shown above in figure 4. Do not connect in star formation (all Brains to one single point). Armstrong International IOM-776 Brain ®...
WARNING! There are high voltages on the control PCB. Ensure that the power supply to The Brain has been isolated and that the unit has fully powered ® down before removing the cover to the network port. Figure 5: Modbus connector pinout Armstrong International IOM-776 Brain ® Modbus Networking...
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Figure 6: Recommended cable arrangement. Figure 6 shows the connection for the DRV Data Cable or the Cat5 cable (depending upon the connector type of the DRV). The twisted pair Cat5 cable is used to minimize any signal interference. Armstrong International IOM-776 Brain ®...
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An end of line termination jumper (CN10) is provided in instances where long cable distances or transmission line reflections are causing poor/unreliable connections. If necessary, fit a jumper across the pins to connect the provided termination resistor into the circuit. Armstrong International IOM-776 Brain ®...
The RTU format and registers relevant to the Brain ® The BMS software will need to be using Modbus RTU (Remote Terminal Unit) format in order to communicate with the Brain ® Figure 9: Modbus RTU format Armstrong International IOM-776 Brain ® Modbus Networking...
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DRV internal database is updated with new settings/values. At least 5 seconds should be allowed between Modbus writes and subsequent reads to allow adequate time for the microprocessor to handle the command/ requests as well as physical mechanical movement of parts to complete in response to the request. Armstrong International IOM-776 Brain ®...
The disinfection feature has a specific sequence as all Alerts and Errors are disabled temporarily while hot water is flushed through the DRV. Please read the following section on setting up the disinfection sequence carefully. The DRV 25/40/80’s disinfection feature is a manual process and for safety reasons must be monitored constantly. Armstrong International IOM-776 Brain ®...
Error Temp. Cycle the power off / on to reset the DRV, make sure the blend circuit is at a safe temperature before allowing any outlets to be used). Set to any value e.g. x1. Armstrong Hot Water Group Armstrong International 221 Armstrong Blvd., Three Rivers, Michigan, 49093 – USA Phone: (269) 279-3602 Fax: (269) 279-3130 IOM-776 armstronginternational.com Brain ®...
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