hevans1944
Hop - AC8NS
A recent newby poster, @haqq, asked:
I have a product testing line with 30 products (1KW each) plugged in at the same time and after completion of the test, all these items are plugged off at the same time.
I need to automate this process i.e:
Turn on all the 30 items at the same time
turn off after completion of required testing time
Reset timer automatically to start the cycle again
Kindly guide me how to achieve this objective.
The thread was rightly closed by a moderator because the OP wanted to switch 30 kW of power on and off simultaneously to thirty devices, each drawing one kilowatt. Clearly, the OP has no idea what he is asking!
When a power failure occurs in my neighborhood, after the fault is fixed an electrical utility worker closes a circuit-breaker (a large fuse) mounted high on a wooden power pole, using an insulated stick with a hook on the end to snag the hinged, dangling, cartridge fuse-holder and push it back in place into a matching receptacle. Presumably the fuse has been replaced if necessary. I watched this happen once a few years ago after a car accident took out a utility pole, downing live wires on the road. The power company temporarily disconnected the fuse to de-energize, and allow workers to repair, the downed wires. From the size of the arc (this was a 7 kV distribution line) when the fuse was re-inserted, there must have been a load of several hundred kilowatts on that line... something on the order of at least thirty, perhaps as much as one hundred, amperes of current. But, Voila! All the lights (and motors and space heaters and whatever) in the surrounding neighborhood came on simultaneously! The moral of this story: if you wanna switch a lot of power all at once, you damn sure better know what you are doing.
The key to possibly answering the OP's question lies in the fact that the products being tested are plugged in, perhaps into outlet strips. He wants to power up and test thirty of them at the same time, power the thirty units down, presumably replace them with thirty more products to test, and then power those thirty products up. Wash, rinse, and repeat until the shift is over.
So we can assume that all of these products have power cords with plugs that can be inserted into an electrical outlet of some sort. And they probably all each have a power switch. Current practice is probably to plug them in, one at a time, and then run down the line flipping the power switches on. After the test, someone runs down the line again flipping the power switches off. And after that a new set of thirty products is brought in for testing.
The key to an automation solution may be this: It is probably NOT NECESSARY that all thirty products be powered up simultaneously! They can, in all probability, be powered up SEQUENTIALLY, one at a time, just as if a minimum-wage intern or apprentice was running up and down the line flipping switches and, later, swapping out products to test. If this is true, all we need is a solution that sequences power to thirty contactors or heavy-duty relays or solid-state switches, each capable of switching one kilowatt, which is about the power consumed by a toaster or microwave oven. POC! Any one of those three devices, informally known as a do-dad or (sometimes) a do-hickey will work.
So, @haqq, get a licensed electrician to select and install thirty do-dads suitable for the power drawn by each product being tested. Have the electrician run the do-dad control lines back to a Black Box that will enable each do-dad in sequence, say, at two second intervals. Provide the Black Box with START and STOP buttons.
When START is pushed (momentarily) the sequence begins and ends one minute later with all thirty do-dads energized. When STOP is pressed (momentarily) the do-dads are de-energized in the same sequence: First One ON is also the First One OFF (FOOFOO operation). That way every product runs for the same length of time, and there are no excessive power surges on the plant wiring.
Here at Electronics Point we can help with the Black Box design. Your licensed electrician can purchase the do-dads off-the-shelf at any electrical supply house and professionally connect them to the Black Box and to outlets for connection of your products.
You will still need that intern to change out the products, but we can leave that aspect of automation to another time.
Hop
I have a product testing line with 30 products (1KW each) plugged in at the same time and after completion of the test, all these items are plugged off at the same time.
I need to automate this process i.e:
Turn on all the 30 items at the same time
turn off after completion of required testing time
Reset timer automatically to start the cycle again
Kindly guide me how to achieve this objective.
The thread was rightly closed by a moderator because the OP wanted to switch 30 kW of power on and off simultaneously to thirty devices, each drawing one kilowatt. Clearly, the OP has no idea what he is asking!
When a power failure occurs in my neighborhood, after the fault is fixed an electrical utility worker closes a circuit-breaker (a large fuse) mounted high on a wooden power pole, using an insulated stick with a hook on the end to snag the hinged, dangling, cartridge fuse-holder and push it back in place into a matching receptacle. Presumably the fuse has been replaced if necessary. I watched this happen once a few years ago after a car accident took out a utility pole, downing live wires on the road. The power company temporarily disconnected the fuse to de-energize, and allow workers to repair, the downed wires. From the size of the arc (this was a 7 kV distribution line) when the fuse was re-inserted, there must have been a load of several hundred kilowatts on that line... something on the order of at least thirty, perhaps as much as one hundred, amperes of current. But, Voila! All the lights (and motors and space heaters and whatever) in the surrounding neighborhood came on simultaneously! The moral of this story: if you wanna switch a lot of power all at once, you damn sure better know what you are doing.
The key to possibly answering the OP's question lies in the fact that the products being tested are plugged in, perhaps into outlet strips. He wants to power up and test thirty of them at the same time, power the thirty units down, presumably replace them with thirty more products to test, and then power those thirty products up. Wash, rinse, and repeat until the shift is over.
So we can assume that all of these products have power cords with plugs that can be inserted into an electrical outlet of some sort. And they probably all each have a power switch. Current practice is probably to plug them in, one at a time, and then run down the line flipping the power switches on. After the test, someone runs down the line again flipping the power switches off. And after that a new set of thirty products is brought in for testing.
The key to an automation solution may be this: It is probably NOT NECESSARY that all thirty products be powered up simultaneously! They can, in all probability, be powered up SEQUENTIALLY, one at a time, just as if a minimum-wage intern or apprentice was running up and down the line flipping switches and, later, swapping out products to test. If this is true, all we need is a solution that sequences power to thirty contactors or heavy-duty relays or solid-state switches, each capable of switching one kilowatt, which is about the power consumed by a toaster or microwave oven. POC! Any one of those three devices, informally known as a do-dad or (sometimes) a do-hickey will work.
So, @haqq, get a licensed electrician to select and install thirty do-dads suitable for the power drawn by each product being tested. Have the electrician run the do-dad control lines back to a Black Box that will enable each do-dad in sequence, say, at two second intervals. Provide the Black Box with START and STOP buttons.
When START is pushed (momentarily) the sequence begins and ends one minute later with all thirty do-dads energized. When STOP is pressed (momentarily) the do-dads are de-energized in the same sequence: First One ON is also the First One OFF (FOOFOO operation). That way every product runs for the same length of time, and there are no excessive power surges on the plant wiring.
Here at Electronics Point we can help with the Black Box design. Your licensed electrician can purchase the do-dads off-the-shelf at any electrical supply house and professionally connect them to the Black Box and to outlets for connection of your products.
You will still need that intern to change out the products, but we can leave that aspect of automation to another time.
Hop
