Hi all,
I was wondering if anyone out there has any experience specifying fusible resistors for use as circuit protection in a 3 phase watt hour meter. I've looked around on the web a good bit and have not found any definitive information for how to properly use these things.
Here are my...
Hi all,
I'm in the process of designing a battery powered device to be used in the car. The plan calls for rechargeable batteries with 12V from the car to provide charging. However, I would also like the option of using alkaline batteries. The problem arises if a customer has inserted...
Hi all,
I'm in the process of designing a battery powered device to be used in the car. The plan calls for rechargeable batteries with 12V from the car to provide charging. However, I would also like the option of using alkaline batteries. The problem arises if a customer has inserted...
I'm looking for a clever and simple way to current limit charge some super caps and also allow them to be available to provide pulse power. Let me explain further:
I'm providing 3.6V from a regulated output to a GSM/GPRS modem. During transmission, I need to suppply up to 2A peak for about...
I need to design a very simple soft start circuit for a super capacitor bank (12 4.7F caps in series). The bank will be charged to 24-28VDC.
I'm thinking of using a power resistor, a relay (to shunt out the resistor when the caps are charged) and some simple control circuit. My first...
Hello all,
I am in the midst of a redesign and am coming up against some problems with management regarding E-stop (emergency stop) implementation in a motor drive amplifier. Could someone who has experience with this particular facet of the NEC or UL comment? I originally asked this...
Hello all,
I am in the midst of a redesign and am coming up against some problems with management regarding E-stop (emergency stop) implementation in a motor drive amplifier. Could someone who has experience with this particular facet of the UL 508/508 comment? Here are the details:
We...
Hello all,
I am in the midst of a redesign and am coming up against some problems with management regarding E-stop (emergency stop) implementation in a motor drive amplifier. Could someone who has experience with this particular facet of the NEC comment? Here are the details:
We manufacture...
Has anyone ever heard of integrating an AC Contactor inside of a motor controller? We currently use a panel mounted AC Contactor to supply power to our motor drive amplifier. If possible, we would like to integrate this contactor into the controller. However, the current panel mount version...
Is there an easy way to generate a triangle wave for use as a PWM clock using only an oscillator and a few components? I currently am using a astable vibrator circuit (with an opamp) and would like to improve the frequency accuracy.
Thanks
If you run a 3phase source through a fullwave bridge, what DC values of voltage and current would you get? Use 120 VAC, Delta as an example. I've been getting confused about the sqrt of 2 and 3.
Thanks
Has anyone ever seen or used an AC contactor meant to be installed in a small enclosure OR mounted on a PCB? I am looking for an AC contactor (120V 3 phase) capable of 30A AND smaller than a typical panel mount version. My gut instinct tells me that there are no such things, but I needed to...
