Surefire BMS-350, Инструкция по установке и эксплуатации

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MODBUS INFORMATION
7.0 Troubleshooting information
SYMPTOM: The LEDs on the BMS Modbus board do not flash.
DISCUSSION:
The LEDs only flash when intact (complete and correct) packets are received from their re-
spective interfaces. If the data arrives garbled, or if no data is sent, then the corresponding LED will not flash.
The COM LED is between the MCU and the large terminal blocks, and is associated with activity on the Mod-
bus. The BMS COM LED is between the MCU and the small terminal blocks, and is associated with activity
on the BMS board.
POSSIBLE SOLUTIONS:
1. Verify that the cables or wires to the BMS Modbus board are connected.
2. Verify that the wires are connected to the correct pins.
3. Verify that the baud rate for data transmission is in agreement on both sides (for example, if the BMS
Modbus board is set for 9600 baud, then the Modbus master must also be set for 9600 baud).
4. Verify that power is present at the BMS Modbus board.
5. If the Modbus COM LED doesn’t flash, verify that the Modbus master is sending read or write requests.
6. If the BMS COM LED doesn’t flash, verify that the BMS board has power. Under normal operation this
LED should always be flashing if both boards are powered.
SYMPTOM: BMS-350 display flickers during Modbus operation
DISCUSSION:
Due to the hardware constraints on the BMS-350, the LED display will flicker slightly during
normal operation when the Modbus is in use. If the Modbus master polls the BMS-350 for data at a rapid rate,
or transfers many registers during each poll, the flickering becomes worse. If the Modbus is being queried on a
continuous basis, the display and keypad may become difficult to operate.
POSSIBLE SOLUTIONS:
1. Limit the number of registers being read from the BMS-350 during each transfer to about 10 or less.
2. Limit the polling interval to about twice per second.
SYMPTOM: Command status always reads 0x0B when attempting to execute a command
DISCUSSION:
The BMS-350 board must be “unlocked” before any commands that modify the operational
variables will succeed. This is similar to the front panel operation which requires a special sequence to unlock
access to operational variables. A special command is used to allow the Modbus master to remotely unlock the
BMS-350, command 0x01. The unlock will eventually timeout in the same manner as if done from the keypad.
POSSIBLE SOLUTIONS:
1. Execute an UNLOCK command (0x01) before attempting to execute any command that changes an opera-
tional variable (e.g. sets a low temperature limit). See the example in Section 4.
Note: When changes are made, re-set/re-start system by powering OFF and powering back ON.