I'll rewire before plugging in a big hot plate. Below is the magic Python code. Again, can't get much easier than this. I've also attached the code in a file called "Test. The Vac can really bite so be careful! Hope this helps - Thanks, Jim. Just a thought. I'm building a circuit in this configuration, that will first turn on the front light of a haunted house mirror, count 30 seconds, then turn it off, turn on the back light, and take a picture with a webcam: I'll sense the switch with one of the other serial lines.
I just built a similar device to switch off my old analog stereo gear no remotes when I put my computer to sleep.
Just tapped into the 5V line on a spare PC power connector. The hand drawn diagram was very helpful. Reply 12 years ago on Introduction.
That is a cool idea. I wonder if I could use my laptop's USB port? I'm assuming it switches off too when entering into sleep mode. I could use that to switch off my space heater I use under the desk. Nice idea, Jim. Reply 10 years ago on Introduction. Pics of my build mentioned above. I used two small 3A relays one for each plug.. Really nice.
I like how everything gets packaged into a plastic box. Being a computer guy Vac always makes me nervous. Having everything sealed up is nice. I learned the hard way that the large module must be bolted to a heat sink. I'm not sure about the small modules you are using. But, packing them inside a small box might be a problem. Based on your mounting, I would derate them down to 1 amp. Looks good, Jim. I know this is an old Able but what would a circuit look like if you would use a parallel port instead of serial?
LPTs use multiple data lines 8 instead of the serials one line. By comparison you can use lpt1, 2, and 3 with just 3 cards, where you need a serial port for each control port. USB to serial dongles would allow for more then 4 easily added ports.
Do you think you could email a simple. This was really intended as a quick and easy way to control a single Vac device. These capacitors will reduce the chances of Electromagnetic Interference with our controller and prolong the operational life of relays. No products in the cart. Please note that images above may contain product not included with purchase. Facebook Twitter Youtube Github.
Buy Now. Relay Options. Solid State Relays Option. Wiring Diagrams Click to Enlarge. Introduction to Relay Control This video will guide you in determining which relay controller you need for your application as well as a general overview of the differences between Relay Options. Choosing a Solid State Relay Please examine the datasheet of each solid state relay carefully, as SSRs do not function exactly like mechanical switches. Special Order Item — Extended Lead Time This product is considered a special order item and lead times will be increased over our standard lead time of business days.
Learn More. Would you like a power supply? Unless otherwise specified, the solid state relays in this document refer to normally open solid state relays by default. When the control signal is applied directly or through the preamplifier to the coil of the reed relay, the reed switch will close at once and the thyristor switch will be activated to make the load conduct.
The transformer can convert the low power control signal from the primary coil to the secondary coil to generate a signal for driving the electronic switch. After processing by rectification, amplification or other modifications, the signal from the secondary coil can be used to drive the switching component. The optical coupler is an opto-isolator that consists of an infrared source usually, a light-emitting diode, or LED and a photo-sensitive semiconductor component such as a photosensitive diode, a photo-sensitive transistor, and a photo-sensitive thyristor.
According to the different components Figure 4. The photo-semiconductor device detects the infra-red radiation from the LED, and then produces a signal to drive the semiconductor switch.
Compared with reed relay and transformer, the optical isolator has better physical isolation ability, to ensure the electrical insulation between high voltage output load circuit and low voltage input signal circuit. And on account of the excellent isolation performance and very compact size of the optocoupler, the optocoupler solid state relay is used in a very wide range of applications.
The input and output circuits of the hybrid solid-state relays are composed of an SSR relay and a reed switcher or a micro-electromagnetic relay in parallel, controlled by different control signals Figure 4. Since the electronic switch has no moving parts, it can switch the load stably and quickly, and does not generate an arc due to high line voltage or heavy surge current during switching.
After the load current is generated, the EMR will be controlled by the control signal 2 and switched on. According to different circuit structure, the solid-state relay can be divided into Discrete Structure Type solid state relays and Hybrid Structure Type solid state relays. The discrete structure solid state relays are mostly assembled by discrete components and printed-circuit board , and then packaged by epoxy resin potting, plastic sealing or resin wrapping.
The hybrid structure solid state relays use thick-film combine technology to assemble discrete components and semiconductor integrated circuits IC , and then encapsulate them in a metal or a ceramic housing. According to the performance, the solid-state relay can be divided into the Standard Type solid state relays , and the Industrial Type solid state relays. The rated current of the standard solid-state relay is generally 10A to A, and the rated current of the industrial solid-state relay is relatively large, can be 60A to A or larger.
Therefore, the industrial SSR relay can meet the strict requirements of the industrial environment and industrial machinery. The plug-in solid-state relays with many package standard like SIP, Mini-SIP, and DIP , can be directly soldered on the printed circuit board, relying on natural cooling, without the need for a heat sink; the flange mounting solid state relays require the additional metal plate or heat sink to dissipate heat.
The latching relay can keep conducting and continuously output the control signal even if cutting off the control current, and it can only be turned off by inputting the reverse current or the off button. The latching is usually used in high-voltage circuits to avoid the expansion of accidents. The basic parameters of solid-state relays fall into three categories: Input Parameters, Output Parameters and Other Parameters.
When the input voltage the voltage applied to the input terminal is greater than or equal to the turn-on voltage, the output terminal will be turned on. When the input voltage the voltage applied to the input terminal is less than or equal to the shutdown voltage, the output terminal will be turned off.
Strictly speaking, the zero-crossing voltage is not a voltage point but a voltage range that determined by the internal components of the zero-crossing relay, which is typically very low and almost negligible. If the power supply voltage is below the zero-crossing voltage, the zero crossing relay will not be turned on; and if the voltage is beyond the zero-crossing voltage, the zero crossing relay will be in the on-state. This parameter is an indicator of the quality and performance of solid-state relays.
The smaller the output voltage drop and the output leakage current, the better the solid-state relay. Inrush current , also known as overload current, input surge current, or switch-on surge current, refers to the non-repetitive maximum or overload current value that the device will not be permanent damage and the output terminals can withstand, when the solid-state relay is in the on-state. Power Consumption , refers to the maximum power value consumed by the solid-state relay itself in the power-on state and the power-off state.
This is also an important parameter to judge the performance of solid-state relays. The shorter the turn-on time and the turn-off time, the better the switching performance of the solid-state relay. It can also include the measured resistance value between the input terminal and the outer casing including the heat sink , and the measured resistance value between the output terminal and the housing.
It can also include the maximum voltage that can be tolerated between the output terminal and the housing, and the maximum voltage that can be tolerated between the input terminal and the outer casing. In operation, it is usually higher than the case temperature and the external temperature of the component.
The maximum junction temperature is the highest junction temperature allowed by the output switching component. Through this chapter you will learn how do solid state relays work. Because of the different application environments, solid-state relays have slightly different internal components, but the working principle is similar. The internal equivalent circuit diagram of ordinary solid-state relays is shown in the figure below Figure 6.
The principle of solid-state relays can be simply described as: for the NO-SSR, when the appropriate control signal is applied to the Input Terminal IN of the solid-state relay, the Output Terminal OUT will be switched from the off state to the on state; if the control signal is cancelled, the Output Terminal OUT will be restored to the off-state.
In this process, the solid state relays realize non-contact control of switch states of the load power supply which is connected to output terminals. It should be noted that the input terminal can only be connected to the control signal, and the load should only be connected to the output circuit. They are not compatible with each other and cannot be mixed. Since zero-crossing AC solid state relays are completer and more typical than other types of solid state relays, the operation details of AC zero-crossing SSR relays can help illustrate the complete working principle of SSR relays:.
The most commonly used component in the coupling circuit is the optocoupler with high action sensitivity, high response speed, and high dielectric strength withstand voltage between the input and output terminals. Since the input load of the photo-coupler is a light emitting diode LED , this makes the input value of the solid-state relay easy to match the input signal level of the control device, and make it possible to connect the input terminals of the SSR relays directly to the computer output interface, that is, the solid state relay can be controlled by the logic level of "1" and "0".
The function of the Trigger Circuit B is to generate a suitable trigger signal to drive the Switching Circuit D to operate. However, if no special control circuit is added, the switching circuit will generate Radio Frequency Interference RFI , which will pollute the grid by the higher harmonics and the spikes, so the Zero-Crossing Detector Circuit C is specifically designed to solve this problem.
The Snubber Circuit E is designed to prevent spikes and surges from the power supply from causing impacts and disturbances even malfunctions to the switching transistors. Generally, an RC circuit resistor—capacitor circuit, or RC filter or RC network or a non-linear resistor such as varistor is used as the snubber circuit. The varistor , also called voltage-dependent resistor VDR , is an electronic component whose resistance value varies nonlinearly with the applied voltage, and the most common type of varistor is the metal-oxide varistor MOV , such zinc oxide nonlinear resistor ZNR.
R1 is a current limiting resistor that limits the input signal current and ensures that the optocoupler is not damaged. LED is used to display the input state of the input control signal.
The diode VD1 is used to prevent the optocoupler from being damaged when the positive and negative poles of the input signal are inverted. The optocoupler OPT electrically isolates the input and output circuits. The triode M1 acts as an inverter, and constitute the zero-crossing detection circuit with the thyristor SCR at the same time, and the operating state of the SCR thyristor is determined by the alternating-voltage zero-detection transistor M1.
R6 is a shunt resistor used to protect the BCR. R7 and C1 make up a surge absorbing network to absorb spike voltage or surge current in the power mains to prevent shock or interference to the switching circuit. RT is a thermistor that acts as an overheating protector to prevent solid state relays from being damaged due to excessive temperatures. VDR is a varistor that acts as a voltage-limiting device that clamp the voltage and absorbs excess current to protect the solid-state relay when the output circuit is overvoltage.
The AC zero-crossing solid state relay has the characteristics of being turned on when the voltage crosses zero and being turned off when the load current crosses zero. Please note that the relay modules are NOT shipped with back emf suppression devices pre-installed.
The exact kind of suppression device and the parameters of the selected device can vary depending on the load itself. It is obvious that it is impossible for us to predict these parameters and design required back emf suppression device and incorporate that on the board. So we believe this is a task best left to the module user. Numato Systems Pvt Ltd reserve the right to modify products without notice.
Product does not support both AC and DC at the same time. What are the serial parameters I need to use when communicating with this board? Since this module uses USB as the underlying transport mechanism, most of the serial parameters do not affect the communication. You can leave all parameters to any legal value Eg: , , etc… for baud rate except Flow control. Where do I find driver for this product? There will be a link to download windows driver.
Linux does not require driver installation since in most cases they are shipped with the driver pre-installed. Why there is no. All Windows versions with the exception of Embedded Editions has this driver binary installed by default. Does this product work with Linux? Yes, this product works with Linux. Please see more details on how to use this product with Linux elsewhere in this document. Does this product work with Mac OSX? Yes, this product works with Mac OSX. Please see more details on how to use this product with Mac elsewhere in this document.
What are the serial terminal software that this product work with? This product works with a lot of different Serial Terminal software. Some examples can be found elsewhere in this document. Different Serial Terminal software are written by different developers with different purposes in mind. So you may encounter some software that may not work with this product.
But usually alternatives are available in most if not all cases. The GPIO looses its previously set value when trying to read the status. Why it is so? When you are trying to read the GPIO, it needs to be put in input mode.
In input mode, the GPIO will go to high impedance state and thus looses the previously set value. If it does, most likely you should be able to use that language with this module. What is the connector marked as ICSP on this module? This connector is used to program the on-board microcontroller. This connector is primarily intended for factory use. I need a customized version of this product, can Numato do the customization for me? Yes, we can definitely do customization but there may be minimum order requirements depending on the level of customization required.
Please write to [email protected] for a quote. Where can I buy this product? We accept major credit cards and Paypal and ship to almost all countries with a few exceptions. We do have distributors in many countries where you can place your order. Suggest edit. How to use the module. Driver available for download on the product page. Also we have a large set of sample code to help you with All aspects of the above steps are covered in the following sections including step by step demonstration.
Connection Details. USB Interface. Relay Contacts. DC Power Supply. Driver Installation. The following video demonstrates how to install the driver on Windows Windows Embedded Editions. Locate winemb-inf-mdmcpq. Sending Commands. The command set. This product supports a very simple command set that is designed to be less cryptic and easy to use manually using serial terminal emulation programs or through a program written in many supported languages. List of currently supported commands.
The simple set of ASCII based human readable command set supported by this module makes controlling relays easy with any off the shelf Serial Terminal Emulation program like Hyper Terminal or Teraterm. Connect the module to the computer, install driver and note down the name of the new serial port that appears in the device manager.
Open Hyper Terminal and select the serial port corresponding to the relay module. Click OK. A new window will pop up where the serial port settings can be changed.
0コメント