For older Lemur models using the BJ## or NX## logic board

Lemur Low Paper SQ Opto Indicator Input Kit P/N S424027-JST


Each kit comes with the following: 

  • Mini Jack JST low paper 3.5mm connector (already installed if ordered with a new printer). 
  • Gold SQ load opto (alignment tab removed from opto holder) and mounting hardware (#2 screw and Nylock nut).  
  • 36” connection cable 

Note: Sensor may be different from about photo

Many of the BOCA roll holder kits already have mounting locations for the low paper sensor.

The sensor is installed in the following manner:

Insert the screw into the countersink side.

Attach the sensor, flat washer and ¼” nut onto the screw. Make sure the tab on the sensor aligns with the slot in the roll holder arm and tighten the nut.

If the paper low SQ opto is to be mounted on the side of the ticket locator tray to the customer’s specified height. The distance from the SQ opto eye to the side of the ticket stock should be no greater than .125” (3.18mm) but may be less. Below shows one possible mounting configuration. The opening may be round or square but must be large enough to not short any of the components on the board to metal.

The Mini Jack low paper cable is installed as follows if the printer does not already have one: 

Gain access to the main logic board.

Screw the 3.5mm jack connector into the hole that is just above the USB interface port.

The other end connects into JDC2 JST connector on the main logic board.

Put the printer back together.

In the FGL printer a low paper condition is signaled when the printer returns a low paper status message (In Hex 0F, in decimal 15) to the host computer. The low paper condition is detected when the SQ opto is no longer able to detect the ticket stock. Once the low paper status is returned it will not be returned again until the triggering condition has been reset. This is accomplished by loading stock so the opto eye is covered and cycling printer’s power.


The host computer can also solicit the current status of the printer by sending an FGL status request (<S1>) command. The printer will respond with a paper low status if the paper low state has been reached and the printer is online (paper out hasn’t been reached) otherwise is will return an X-ON status


Once the low paper kit is installed you may check that the SQ opto is working properly as follows:


  1. Unscrew the black plastic mini jack plug cover so you may get access to the wires.
  2. With the printer powered off plug the mini jack connector into the printer.
  3. Power the printer up. Using a Digital Volt/Ohm Meter (DVOM) take a voltage reading at the green wire.
    You should see the below voltage levels.
    1. Less than 1.00VDC when there is no ticket stock in front of the SQ opto.
    2. Greater than 3.60VDC when there is ticket stock in front of the SQ opto.
  4. Once you have confirmed the opto is working properly then power off the printer and screw the black plastic mini jack plug cover back in place. If you do not get the above readings then check to make sure the distance to the optos is correct.