First, the power sequencer introduction
The power sequencer, simply by means of the internal control circuit of the device, sequentially turns the power output on or off according to the established program, and the power supply voltage and the load device are managed. The voltage can be accurately monitored and the volume is smaller. From 1U to 3U standard racks, there are mainly 8, 10, 12, 16 channels. Widely used in automatic control, television broadcasting systems, audio broadcasting, power facilities and other systems.
In the audio equipment, the correct shutdown procedure is to turn off the power amplifier first, and then turn off the pre-stage equipment such as the exciter, the crossover, the mixer, etc.; First turn off the power amplifier to prevent the noise from being generated by the front-end equipment and damage the speakers and amplifiers. By using the power sequencer and accessing different switch sockets, it is possible to start the power supply from the pre-stage device to the post-stage device one by one. When the power supply is turned off, the opposite is true, and the various types of electric equipment are effectively and uniformly managed to avoid The man-made error operation reduces the impact of the power equipment switch on the power supply grid and ensures the stability of the power system.
Second, the application of power sequencer in the sound system
Is it used first or not? If in some fixed occasions, such as large venues or performances, the entire system has professional operations, the sound engineer or operator can use the audio equipment very skillfully, and it is completely unnecessary to use the timing switch. After all, the simpler the system, the fault occurs. The lower the rate. Even with the use of the sequencer, its function is relatively powerful, such as multi-level cascading, CPU control, computerized management, etc., stability and power capacity is also relatively large. So in a certain sense, the timing switch is more suitable for beginners.
In most occasions, such as the conference room of the unit, the background music system, the karaoke business place, the middle and low-end Di Bar, the personal home entertainment system, the fixed installation of small and medium-sized venues, and the slow shake bar, etc., there are very few Professional sound engineers are operating, and some are like stage cars, mobile performance sound systems, school public address systems, and also part-time management equipment. The normative operation is not strong, you need to add appropriate timing power management for users. Better mastery.
Facts have proved that in some current engineering configurations, the timing device power supply has almost become a standard equipment. How to properly select, correctly apply, timely maintain and discover hidden dangers in advance is a new subject faced by audio technology practitioners.
Third, understand the key parameters of the sequencer
1) Power input and output: input voltage, input maximum current, output voltage, maximum output current, channel number, socket type.
2) Front panel is the control interface: timing toggle switch; channel status LED indicator.
3) Channel delay interval, generally a fixed value, 1~1.5 s.
4) Switching device: that is, the internal power on/off controller, which is generally composed of relays.
5) Standby power switch: Prevents the controller of the sequencer from losing control. When the switch is turned off, all channels are directly connected.
6) Control input: There is generally 1 IO control interface (TTL level) for detecting whether the output load is short-circuited.
7) Control communication: RS232 control interface, used for cascading and management between sequencers, that is, system expansion, transmission of address code and status information.
8) Other parameters: such as equipment weight, specifications, working environment requirements, etc.
Some powerful timing devices also include voltmeters, air switches, and power supply filtering.
Fourth, the use of precautions
1) Connect correctly according to the requirements, pay attention to the switch sequence and power capacity, and the system connection one-to-one correspondence, it is best to do the label on the power plug, check before each use, conditional backup of the sequencer.
2) For large power consumption equipment such as power amplifiers, due to the large operating current, the connectors need to be checked regularly, especially in mobile performance applications. The vibration during transportation will cause the plug to loosen and see if there is oxidation in the case of wet weather. Phenomenon, to avoid poor contact or increase resistance after oxidation, heat damage.
3) Mainly refer to the number of access devices, the maximum power consumption of high-power devices such as power amplifiers to determine the timer selection, socket type and access current are different, respectively, connected to the mixer, audio processor, peripheral devices, before and after Level power amplifiers, etc., can not only meet the actual work needs, but also avoid waste of resources.
4) In the cascading use and expansion of the equipment in many cases, it is necessary to pay attention to the total current, it is best to control the power supply with the lighting.
Fifth, the extended function and control mode of the sequencer
In addition to the basic functions of the sequencer, some special models also have extended functions. Here is a clean power sequencer (PROBASSCO VS-801) as an example.
The sequential power supply first has the elimination of electromagnetic interference between systems (especially the lighting system), which has a significant effect on the audio system to improve the sound quality. Followed by MCU control, intelligent control methods and control interfaces: key lock, manual button, infrared remote control three direct modes; emergency / external control level control, infrared control signal input, standard RS232 serial port (IN / OUT The external interface control mode can even control the system of one or more machines through the PC control software; in the timing control, any one of the channels can be set to the normally open mode, and any phase can be set when the sequence is working. The switching action time between the two adjacent channels (with the longest time limit) is functionally similar to the function of the programmable timer, which satisfies some special user application requirements.
Sixth, the sequencer general troubleshooting
Under normal circumstances, the sequencer is faulty. It is very likely that the internal switch is in poor contact and damaged. After the power is turned on, it will listen to the sound of the pickup. Use a multimeter to measure the output. In case of emergency, straight through. In addition, the plug of a certain road is loose and the contact is poor.
Check the input power indication before work, input power is normal, check the output channel indicator, and the control panel is normal. There is no abnormal smell, and the problem is to cut off the power quickly. Control and low-voltage control parts are relatively rare, and the fault phenomenon is that the power supply is normal, and there is no response when the power is turned on.
NLW-ECL Module (SM Fiber)
Nlw-Ecl Module Sm Fibe,Sm Semiconductor Lasers Modules,Laser Module Exchange,Laser Module For Cutting
AcePhotonics Co.,Ltd. , https://www.cgphotonics.com