Hello,
I am new to this forum and subject and have a couple of questions before I place an order.
My project is as follows:
I am converting an autopilot from direct electric drive via 12 v DC reversible motor driven by a PWM output from the course computer.
the new 12 vDC reversible hydraulic motor requires more current than the existing computer can drive without damage. My intended solution was to use ielectronic interposing relays in the form of an H bridge to source the 12 v DC for the hydraulic motor. I see the Cytron MD30C (part no. RB-CYT-133) has the voltage and drive current capabilities but it is not clear to me from the literature whether my course computer outputs can drive the H Bridge directly. I have seen discussions that suggest there must be some kind of isolation to prevent both bridge halves from conducting when in the off/quiescent state.
I believe that the computer output is essentially a two wire bi-directional PWM voltage waveform which turns the existing geared motor in the direction called for b y the course computer.
Could anyone point me in the direction of information which might help clarify my question. My only alternative is to purchase the H Bridge and try it but the engineer in me doesn’t prefer that route…
Hi,
First, please note that we have split this post from the Basic Dual motor driver/controller topic as both subjects/issues are not related.
The 30A 5-30V Single Brushed DC Motor Driver is intended to work either with a microcontroller (that can generate a PWM signal for speed control) or with a potentiometer (the onboard potentiometer or an external one).
If you are looking to control your motor with a computer, you can use a USB Controlled DC Motor Driver.
The Pololu 24v12, 5.5-40V, 12A Motor Controller or the RoboClaw 2x30A, 6-34VDC Regenerative Motor Controller might work for this.
One more time if I might: the existing course computer puts out a PWM +12 v DC CW and -12 V DC CCW. I need to drive a reversible pump motor that requires more than the 10 A the controller is capable of driving. I could use two parallel DPST relays with diodes on the + input to each relay but I was hoping to duplicate this function electronically to avoid eletromechanical wear and time delay.
Is there a device you can recommend that is capable of sensing direction based on input line polarity and replicate the speed control by passing the input PWM pulse?
We unfortunately don’t offer a DC Motor Controller that can do what you described.
What is the course computer you are using to generate the PWM signal ?
The course computer is Raymarine autopilot course computer. It puts out a +/- DC 12 V on two wires to directly control a 12 V DC motor. It is rated max 10 A at 12 V DC. I want to convert my autopilot to hydraulic linear actuator which is driven by a reversible 12 V DC pump motor. The existing controller works fine other than its limited output. While the motor I am replacing has not got enough power to hold the helm under heavy sea state it works fine in calmer weather. Unfortunately that is not when I need it most. The hydraulic motor is rated 16 A max and will take the two wire output from the course computer under normal conditions but under heavy load I am concerned the course computer output driver will blow. There must be a solid state analog to my contactor solution…or a way to interface to an H Bridge driver to get the higher current rating. Anyone have any suggestions?
