Made in USA Flag All board products Proudly made in USA!

Manufacturer of computer controlled relay, I/O and custom boards for commercial and industrial applications.

Please Note: Pencom will be closed from September 12th thru September 23 - we will re-open on September 26

** Please note supply chain shortage update 09-07-2022 -  a limited supply of the backordered parts will be arriving around September 28th for the USB boards - more parts are on order:   We have many backordered boards that will be produced first - notifications will go out to customers to verify the orders are still valid.

There will be production delays due the volume of the backorders

Due to the supply chain shortages we have been having a difficult time obtaining parts to produce our products.  Some of our parts have been on order for 12 months  Some parts are being received for certain products and we will do our best to fulfill what we can.

In addition we have been experiencing problems with our email system and many emails were never received on the following accounts our and, this has been happening for some time and we were unaware since it is happening sporadically. 

We have created two new accounts to use until we can determine the problems we are having with our system and please use these emails to contact us.

Other email address have been the same problems and we will work to correct these too.

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RS232 Control

An RS-232 serial port was once a standard feature of a personal computer, used for connections to modems, printers, and other peripheral devices.  

In modern personal computers, USB has displaced RS-232 from most of its peripheral interface roles due to the low transmission speed, however USB was designed for desktop usage and not robust enough for industrial uses - due to the problems operating in noisy environments, and being especially susceptible to inductive noise.  In addition connectors for the USB devices are not fastened securely with a locking mechanism, and have a limitation of 16 feet.

Therefore RS-232 devices are still widely used, especially in industrial machines, networking equipment, and scientific instruments, due to their ability to operate in noisy industrial environments.  The RS232 device specification is 50 feet minimum, however they will work many times this distance in mild noisy environments.

Many computers do not come equipped with RS-232 ports and must use either an external USB-to-RS-232 converter or an internal expansion card with one or more serial ports to connect to RS-232 peripherals. 

If USB control is required in high noise environments, one of our Isolated USB to RS232 converters can be used with a RS232 relay board to help limit the inductive noise that affects the USB devices, these converters connect directly to the modular cables that we use on the RS232 relay boards.