What is the difference between positive and negative logic in digital I/O circuits?

  “When a circuit requires logic 1 to operate, engineers may refer to this condition as positive logic. Thus, the more positive voltage causes the action to take place. On the other hand, if a circuit requires a logic 0 to cause action, this type circuit is referred to as negative logic. There is nothing […]

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What is the difference between SeaIO and SeaMAX software?

  SeaIO is the classic software driver that supports our PCI Express, PCI, PC/104, ISA, and classic USB digital I/O devices. SeaMAX is the driver for our latest digital I/O data acquisition products, including SeaI/O modules, SeaDAC modules, and SeaDAC Lite modules.  

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What is the difference between SeaLINK 820x and 820xFX digital I/O adapters?

  Sealevel strives to minimize the impact of component obsolescence to our customers. When a component is discontinued by a vendor, Sealevel’s goal is to redesign the product to offer a form, fit and function replacement. In most cases this is completely transparent to the customer. However, in the case of our 820x digital I/O […]

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What kind of output is best for controlling the power to a DC motor?

  Open-collector outputs with circuit protection are the best choice for controlling power to devices with highly inductive loads such as DC motors, solenoids, and high-current relays. Switching off inductive loads can induce a voltage spike capable of causing damage to relays, digital outputs, or the DC motor itself. Both SeaI/O-530 and SeaI/O-540 modules have […]

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What type of relay should I use to control a 24 VDC solenoid?

  The Form C relays contained in many Sealevel digital I/O products are the best choice for switching highly inductive loads like solenoids. Other relays, including reed relays and solid-state relays, are not well suited for this application. Reed relays may work temporarily when switching inductive loads, but will be prone to pitting and welding that […]

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What wire colors are used for RS-485 on a SeaI/O module?

  We assume that you want to use a standard (CAT5/6 EIA/TIA-568B) Ethernet patch cable to connect to the RJ45 pass-through connector on the side of the SeaI/O module, due to their low cost, wide availability and various lengths. If you are connecting a SeaI/O module to another RS-485 device, plug one end of the […]

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Where is the description of the SeaIO API?

  This is located in the help file when SeaIO software is installed. From the Start menu, locate the SeaIO folder and choose SeaIO Help. In the contents you will find a section titled Programmers Interface. This will explain the Usage and API references that fully document the SeaI/O API, including samples and descriptions of […]

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Where is the description of the SeaMAX API?

  This is located in the API Documentation file when SeaMAX is installed. From the Start menu, locate the Sealevel SeaMAX folder and choose Documentation and then SeaMAX API Documentation. For Function call descriptions and examples, select the link titled SeaMAX API. This will explain the Usage and API references that fully document the SeaMAX […]

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Which Sealevel digital I/O products are compatible with "open-collector" outputs?

  Depending on your application, Sealevel digital I/O products with either optically isolated inputs or TTL level signaling can be used. Sealevel products with TTL inputs require tight coupling and will work for simple applications where there is a short distance between the input and output modules. TTL signals require voltages of 5 VDC. Sealevel […]

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Why are solid-state relay modules different colors?

  The color is used to identify the type. The open-standard color scheme was developed by Opto 22 in 1978 to help identify the four basic types available. The universally accepted colors are: Red: Output DC (ODC) White: Input DC (IDC) Black: Output AC (OAC) Yellow: Input AC (IAC) Sealevel offers a variety of relay […]

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