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Each output is nominally rated at 3ADC continuous with a start-up (intermittent) rating of 15A. The power supply can be 12V to 24VDC.
The greatest strain is placed on the board, and on the power supply, if the motor is mechanically prevented from rotating ("locked rotor") and has the full power supply voltage applied to it. A similar strain occurs for a short while if the motor is turned on at full voltage, before it has started rotating. As the motor spins up to speed the "dynamo" voltage generated by the motor cancels out much of the supply voltage, and the current drops off. The start-up strain on the SPice10213 will be less if the motor voltage (PWM) is ramped up rather than turned straight on at full voltage.
You can estimate the locked rotor/startup current by measuring the motor resistance. If you use a normal multimeter, measure the resistance of the test leads and deduct from the reading you get off the motor using the same leads. Typical motor resistances are in the low ohms or less than an ohm range. The larger the motor the smaller the resistance. Divide the resistance in ohms into the supply voltage to get the locked rotor current in amps. You may also be able to get the locked rotor current off the motor name plate or data sheet.
If the locked rotor current is less than 15A the SPice10213 should unconditionally be able to drive it. If it is over 15A, it may still be OK but you must be aware of the risks. If you can guarantee the motor can never suffer a locked rotor, or if you are prepared to blow up the SPice10213 if it does lock, then providing the continuous motor running current is less than 3A it may still be OK. You should however make sure the motor gets ramped up to speed rather than getting turn on suddenly at full power. The main hazard if the board is overloaded is that the power FETs (transistors) will over-heat.
The reversing relay is rated to switch 5A. It can carry more, as long as it isn't expected to switch more. The 4.7 ohm dynamic braking resistor ensures that this level is not exceeded, providing your program turns off the voltage drive (PWM) before switching the reversing relay. The programming examples cover this.
Note: The product warranty on this board does not cover blown up output transistors.
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