0

# What is china's favorite game?

I only know two of lots. but the two is... oragami and kung fu

# How does an open circuit occur?

An open circuit does not work. You need to have a complete circuit for the electrical current to flow back to its source. For example: An open circuit occurs when a series fuse blows or a connector is unplugged.

R - Red

Y - Yellow

B - Blue

# What is the formula to calculate secondary current?

The secondary current is calculated by dividing the secondary current by the impedance of the load. This value shouldn't exceed the secondary-winding's rated current except for short periods of time.

# How the infrared burglar alarm works?

Transmitting binary ones and zeros via IR (infrared) light is not as complicated as it may appear at first glance. Just as radio stations transmit information using radio waves, infrared devices transmit data using the infrared frequencies of the electromagnetic spectrum. Also, just as you need a compatible device to listen to a radio broadcast, you must have a device capable of understanding and translating incoming infrared signals. All sending and receiving IR devices contain small, dark windows called IR ports. Inside these ports, transceivers (a combination of a receiver and transmitter) send and receive data using the IR frequency. After a device's CPU (central processing unit) sends the binary ones and zeros to the software controlling the IR transmission process, that information is converted into pulses of IR light. The software then forwards the data to the device's transceiver, which transmits the IR signals to another IR port. The receiving device's IR software converts the infrared transmission back into binary digits. IR devices transmit the binary ones and zeros according to a protocol set by the IrDA (Infrared Data Association; http://www.irda.org). For high-data transmissions, such as from a laptop to a printer, both devices must be within a few feet of each other and the IR ports must be within each other's line of site. The data is sent in a 30-degree wide cone from one IR port to another. Depending on the IR software, a pulse of light could represent a digital one, while the absence of a pulse of light could represent a digital zero. High-speed IR devices don't actually transmit data in a serial string of ones and zeros, however. Rather, bits of data are sent in groups to speed up the transmission process.

reference:(http://www.smartcomputing.com/articles/archive/r0403/30r03/30r03.pdf?guid=) *note: Search More You Damned Fool!!!

# What safety precaution is required for starting an electric motor?

1. Proper cable connection through a suitably rated starter.

3. Mechanically stable mounting and aligned well with the driven equipment.

4. Safety precautions to be taken based on the equipment driven by the motor.

# What components in a computer contain gold or platinum?

To use for electrical currents or possibly store information. You can extract the gold be getting the computer chips and putting them in a glass jar with Mulatic acid and hydrogen peroxide. It should desolve the metals except the gold

# How many volts can transmission wire carry?

Transmission voltages are usually considered to be 110 kV and above. Where higher capacity is needed the line conductors are grouped in to three and four groups per phase leg. Voltages less than 33 kV are usually used for distribution by the utility companies.

The utility company then supplies the transformers to drop the voltage even lower so that it can be brought to homes to be used by their customers.

The transmission lines are of a composite arrangement. ACSR, Aluminium Conductor Steel Reinforced.

# How many watts can install in 1000 microfarad?

Zero watts can be installed in 1000 micro farads. Watts are the product of amperage times volts. Micro farads is a value used in talking about capacitance.

# How many kw is in 125 kv?

I can see that the best answer has already been given (the units aren't even remotely close). But suppose that what the asker meant was 125 kVA? In that case, it can be answered.

VA (or Volt-Amperes) is what's used to represent current consumption when the circuit runs on any form of alternating current (AC). Watts (W) don't apply, because of the inherent properties of a changing waveform. To properly calculate the actual put-into-use (or effective) power, one would have to take the entire circuit into account.

But, to answer the speculated question, I would say - anywhere between 125 kW and 0 kW, depending if the load is purely resistive, or purely capacitive in nature, respectively.

# Why LDR used in PIR sensor?

industrial automaton

# How will a 3 phase panel give you 110 volts and 220 volts?

A three phase panel will not give you 110 and 220 volts. A three phase four wire panel will, but not at these voltages. The nearest voltages will be 120 and 208 volts. The 120 volt is the wye voltage of 208 volts. 208/1.73 = 120 volts.

A single phase three wire panel will give you 110 and 220 volts.

# What size of fuse should be used for 75 hp 415v 3 phase motor connection?

To answer this question, wire size is rated in the amount of amperage that it can legally carry. Fuse sizing is based on the amperage that the wire carries.

The formula to find amperage when the HP is known is I = HP x 746/1.73 x E x %eff x pf.

A standard motor's efficiency between 5 to 100 HP is .84 to .91.

A standard motor's power factor between 10 to 100 HP is .86 to .92.

Amps = 30 x 746 = 55950 = 55950/ 1.73 x 415 x .87 x .87 = 55950/550 = 101 amps.

The electrical code states that a motor conductor has to be rated at 125% of the motors full load amperage. 101 x 125% = 126 amps

A #2 copper conductor with an insulation factor of 90 degrees C is rated at 130 amps.

Fusing for this motor will be, non time delay fuse 300 amps, time delay fuse 175 amps or a circuit breaker rated at 250 amps.

# Which size of motor requires a solo run test?

All motors should be test bumped to check for rotation. Larger three phase motors should be disconnected from the load before this is done.

# What is meant by load in diesel generators?

Any device that uses the generator to supply its operating voltage is electrically classed as a generator load.

# How do you step up 12vac 3phase to 24vac 3phase?

Twelve volts is not a common three phase voltage. Assuming that this is a hypothetical question any 1:2 ratio transformer will do the job.

Rather common for electric fork lifts

very small ones use 12v (hand stackers,pallet jacks)

larger ones are 24v 36v or 48v

the original transformers on the chargers usually run from 480V

and the chargers are specifically designed for the battery

most chargers use half wave rectifiers in a star configuration

600A thru a .7v drop for a diode is 500w loss, full wave is 1000w

regulation is switched from the primary side since its easier to handle the low current

# How do you determine a 3 phase motor and each winding?

To see if the motor is three phase or single phase look at the motor's nameplate. There it will tell you what the voltage needs to be and what system phase the motor needs to be connected to operate properly.

# How do you stop the second compressor in a 7.5 ton dual compressor unit from cycling on and off every 10 seconds?

I assume that it is an air compressor (dual units - two compressor motors) used to provide pressurised air to operate some valves and devices in a industrial plant. (Because it is not clear in the question)

Normally the compressor is designed to operate in "load and unload " mode through few solenoid valves, if not equipped with Variable frequency Drive.

If the compressor is equipped with variable frequency drive, then it is designed to run in "load and Unload" mode using the VFD for variable speed to switch between load and unload mode.

In both the cases, load and unload mode are trigged by pressure switches or pressure transmitters at a preset differential values. Air compressor runs on "load" mode till pressure reaches the preset maximum value. It then switches to "unload" mode till the pressure reaches the minimum preset value. Once the minimum value is reached, it switches again on "load" mode. The cycle continues, but motor does not start - stop during these modes.

Air pressure is a function of consumption in the usegae points, which keeps on reducing gradully basis the consumption. How quickly or slowly the pressure reduces - depends on the rate of air consumption.

There could be several reasons for the second compressor to go on - off every 10 second.

Check the "load - unload" pressure setting on the conmpressor. Increasing the differential setting a bit more, will increase the on-off cycle time. Check the requirement and data sheet before doing so.

Check the consumption, whether it is genuine or waste (air Leakage). Check what is happening the first compressor. If it runs on "load" mode all the time then the actual consumption is just more than the capacity of the one compressor, hence the second one comes on but goes off every 10 seconds, since the consumption is just slightly above the first compressor capacity.

If the waste or leak can be arrested, only one compressor can manage the load, most of the times.

Check the control philosophy the compressor, whether it is designed to go on - off or it is designed to switch between load and unload mode - corresponding to differential pressure setting. (Generally Load and unload mode does not turn the motor on and off, but during unload mode, it keeps running at almost no load current and during load mode it takes normal load current)