My SFT 881 won’t feed the proper input into my third-party equipment

Overview:

Installing a pull-up resistor ensures that the SFT 881's Pulse Output terminal is properly powered and can communicate with third-party equipment. If your equipment already has a built-in pull-up resistor, no external one is needed. Otherwise, follow the steps below to install one and ensure proper signal transmission.

Steps to Check for an Existing Pull-Up Resistor:

1. Check the Manual
   • Refer to your third-party equipment’s manual to see if a pull-up resistor is installed in the counter.
2. Test with an Ohmmeter
   • With the power off, use an ohmmeter to measure the resistance between the Pulse Input and Voltage Input terminals of the Pulse Counter.
   • If the reading is between 1KΩ and 10KΩ, a pull-up resistor is installed, and no further action is needed.
   • If there is no reading or a much higher resistance, you will need to install an external pull-up resistor.

How to Install an External Pull-Up Resistor:

1. Choose a Resistor
   • Select a 1KΩ resistor, which is suitable for most applications.
2. Connect the Resistor
   • Connect one end of the resistor to the Pulse Output terminal on the SFT 881.
   • Connect the other end of the resistor to the same power source supplying the pulse counter.
3. Connect Ground
   • Ensure the ground of the Pulse Output terminal is connected to the ground of the Pulse Counter.
4. Power Up
   • Once the connections are made, power up the system. The solid-state switch in the SFT 881 will now generate pulses that the counter can read.