Practical techniques for air conditioning maintenance (main electrical control component)
Introduction to the ac power control utility
1. Electrical resistance
One. 1 definitions
The conductor, on the one hand, has the ability to conduct electricity, which is called electrical resistance performance, and we call the physical element with electrical resistance, which is effective for communication)。
8. Pressure-sensitive electrical resistance
Made from semiconductor materials having non-linear volt-an properties. The electrical resistance at normal working voltage is very high, which is equivalent to a breakout, a instant high voltage, which is very small, which is equivalent to a short circuit.
Effects: excessive pressure protection, thunderstorm protection and instant pulse suppression。
Main parameters:
Placing voltage: the end voltage of the pressure-sensitive resister (usually 1 ma) when the pressure-sensitive resister flows past the specified current。
Non-linear coefficient (alpha): indicates the degree to which the voltage properties of the pressure-sensitive resistor deviate from om's law. Usually, the greater the value, the better
Alpha values are 25-50.
Flow: . It's useless consumption in lines, and the smaller the better。
Relays
Modus operandi: electromagnetic relays typically consist of steel cores, wires, cortex, contact springs, etc. As long as there is a certain voltage at both ends of the online circle, there will be a certain current flow in the ring, which will have an electromagnetic effect, and the cortex will inhibit the pull to the core of the spring from returning to the spring as a result of the attraction of electromagnetic force, thereby boosting the cotronary action point and the static contact point (the frequent contact point). When the wire is out of power, the electromagnetic insulation disappears, and the cortex returns to its original position at the back of the spring, so that the kinetic contact points and the original static point of contact (often closed). It is thus inhaled and released, and thus serves the purpose of channeling and cutting off electrical circuits。
Effects: switches with low voltage to control high voltage or with small currents to control large currents。
10, step-in
An electromechanical element that converts a pulsed signal to a corresponding angular (or linear) shift. That is, an electrical pulse signal is added to the electric generator, which moves one step。
Ten. 2 main parameters
Step angle: zirconium = 360°/twice value is the theoretical value of the transducer value of each electrical pulse signal。
Activate voltage: with a rated load, the electric power is capable of reaching the maximum rated rate of voltage from static status。
Magnetic voltage: the rated value of the voltage applied in the electromagnetic circuit group。
Magnetic currents: the rated values of currents passed through the electric magnetic circuits。
Tradging rectangular: refers to the maximum output rectangular value when the rotor rotates. It's about the motion frequency。
Space-carrying frequency: the maximum frequency at which a step-by-step motor is activated and stopped.
Aerial pull-out frequency: the maximum non-disturbable frequency is maintained by the space of the walker。
Ten. 3. Rationale
The walk-in machine used on the air conditioner has a quadrupling group on the fixed and can generate step-by-step movement as long as the power flows through the circuits。
Ten. Four, good and bad
Interception between one foot (red line) and other feet was 200 ~ 380。
11. Temperature sensors
Definitions
I don't know. The higher the temperature, the smaller the resistance. For example: ktm-41-c9 (copper) ktec-41-c12 (plastic):
20°c: 25°c: 10°k, 30°c:8. 048k, 40°c: 5. 311k
Test method
The temperature sensor is held in hand to detect its resistance, which is gradually decreasing。
12. Vibrator
Twelve. 1 useful
Stable and select frequency. A/d sampling frequency with air conditioning, clock frequency.
Internal circuits
Its internal equivalent is a high-quality lc-coordinated resonance circuit, as illustrated below. The l in the figure is the equivalent electrical sense (or dynamic electrical sense) during a chip vibration, c is the equivalent electrical cap (or dynamic cap), r is the equivalent electrical resistance (or dynamic resist) and c0 is the sum of the internal caps of the crystal oscillator。
13. Double chip
Thirteen. 1 role
When the power voltage is lower than the working voltage of the microprocessor, there are unforeseen consequences for the microprocessor, usually death machines, program flight, loss of data in sram (static storage). The compound chip is to maintain the microprocessor in a non-working state until the power voltage reaches a certain level and remains stable。
Thirteen. 2 feature parameters
Vdd: power voltage
Vtrip: microprocessor job startup voltage
Voh: reverted signal high electro-tension
Trpu: voh over vtrip time lag
Vdd
Reset
Vtrip
Trpu
Voh
Hardware principles for air conditioners
As can be seen from the chart:
1 power supply component (220v power supply access, transformers, current circuits, 12v directs for relays, 5v directs for chips such as microprocessors, etc.)
2 signal input component (controlled signal reception, ac key, sensor):
3. Signal output control component (showers, indoor fans, walkers, outdoor fans, four valves, compressors)
