MoTeC Global Forum

Greetings Dears,

I am new to M150 and Motec in general. My questions are as follow:
1. Related to M150 power supply 5V and their corresponding 0V, are they internally isolated or can I mix them up?
2. depending on the answer to the first question, the 6.3V does not seem to have its own 0v, so where to connect the other end of the sensors?
3. Same applied for Battery Pos. and Battery neg.? and how are they related to 5v power supplies' current capacity?
4. suppling hall effect wheel speed sensor from 5v would it ruin analog sensors measurements supplied to by the same 5v?

Cheers,
Hisham

Hi,

The 5V+ and 0V rails are isolated internally, whilst they can be shared, if a sensor goes faulty and affects one of the supplies, the M1 will try and ratiometrically adjust the signal from the other sensors on the shared supplies to maintain operation, if you have sensors that share different 5V+ and 0V rails, then this can cause those sensors to misread and potentially affect sensors on the other supplies.

The 6.3V can be connected either ECU Ground or a 0V rail. Most of the sensors that I have seen that need 6.3V will be specified to connect to ECU Ground.

Are you wanting to know the current supply requirements for the M1?

We recommend that rotational sensors are wired to one 5V+ and 0V rail (i.e. A), the engine critical Analogue sensors to another (B) and the remaining sensors to C.

Hi,

Many thanks for your answers. For the current, I need to know how much load I can connect to the 5v supplies before affecting the voltage level? how battery inputs Battery Pos/Neg are related to 5v power supplies? I know sensors usually do not consume current that too high. but I would like to know how safe and reliable my connections are.

Many thanks,
Hisham

Hi,

250mA per 5V+ rail.

The Primary VBatt+ and ECU Grounds need to handle the loads from the Bridge outputs, such as DBW, and the injector currents, the sensor 0V load is almost irrelevant in comparison to this.

Many Many Thanks,
Hisham