Understanding the C8 Board - Part 4

In previous parts of this series, we have covered the very basics and the inputs and outputs of the C8 board.  If you missed these parts, you can find them here:

Part 1 - Power and LEDs

Part 2 - Inputs

Part 3 - Outputs

Here we will cover in detail the jumper configuration of the C8 board.

General Jumper Setting Information

First, it is important to verify the voltage of the power supplies and to set the C8 jumpers before connecting any load.  This is to ensure the proper voltage is sent to the load devices and prevent damage to the devices.  Verify output voltage on each zone before connecting any load.

If you have read the previous parts of this series, you should have a fairly solid understanding of how the C8 should operate.  This knowledge is helpful in setting the jumpers when a manual is not available.  As mentioned in previous posts, it is not necessary to have the function of each jumper's positions memorized - only the overall function of the jumper.  For example, once you know the Red jumper is for FAI, you know that is the jumper to move if FAI is not operating the way you expect it to for a particular zone.  There is no need to memorize that Position 1 is on, and position 2 is off, or that position 2 of the Blue jumper is for a NO input.  As you go through the following sections, take note of the jumper color in relation to its function.

Also remember the correct LED operation - LED lit steady for a locked door, and flashing for an unlocked door.  The goal is to get this correct with relation to the input, then set the output to operate correctly.

Finally, please note jumper positions as they are printed on the PC boards carefully for EACH jumper.  For some jumpers, position 1 is up, while for others, position 1 is down.  Every jumper has a position marker next to it.

Black Jumpers

The black jumpers select whether the output will be a relay contact output or a wet (voltage) output.  Both jumpers should always be set in the same position, without exception.  Use caution when setting these jumpers, as position 1 is different on each jumper.  From the factory, these jumpers come set in position 2, which provides a voltage output.  If a relay output is desired, move these jumpers to position 1.

Yellow Jumper

The yellow jumper selects the voltage to be applied to the zone's output.  Position 1 sets the output to the B1 voltage, and position 2 sets it for the B2 power supply.  In a single voltage system, this jumper will remain in position 1, as there is no B2 voltage present.

In a dual FPO system, as built by LSP, the top FPO will be the B1 voltage.  The bottom FPO will be the B2 voltage.  So if the top power supply is set for 24V and the bottom FPO is set for 12V, then position 1 on the yellow jumper will set the output for 24V, position 2 for 12V.  In an FPO/B100 system, the 24V is on B1, and the B100's output is on B2.

Again, always verify each zone's output voltage before connecting any load to the C8.

Blue Jumper

While all of the jumper settings are equally important, getting the blue jumper set properly is critical to the operation of the C8.  In Part 2, we discussed how the B terminal of the input is a voltage input, while the A terminal is a voltage source.  The blue jumper sets the zone to either activate on the application of voltage, or the removal of voltage on the B terminal.

Position 1 will activate the zone on a removal of voltage from the B terminal.  This is the setting you would want for a NC contact activation.  The NC contact will normally connect the voltage from the A terminal to the B terminal.  When the NC contact opens, the voltage at the B terminal goes to zero, and activates the zone.  This is also the setting to be used for an open collector input - normally, a voltage is present on the B terminal, and the open collector will shunt this voltage to zero to activate the input.

Position 2, is the opposite - an application of voltage will activate the zone.  This is the setting to use for a normally open contact activation.  When the contact closes, it connects the voltage from the A terminal to the input of the B terminal to activate the zone.

To verify the proper setting of the blue jumper, look at the LED status for the zone in relation to the input.  If the LED is flashing when the input is set to unlock the door, the blue jumper is set correctly.  If the output is operating opposite from what is expected, but the LED is operating correctly, then the white jumper needs to be adjusted.

White Jumper

The white jumper sets the output by selecting the NO or NC contact of the internal relay contact.  Position 1 uses the NC contact and position 2 uses the NO contact.  When set for a relay output, this is straightforward.  When set for a voltage output, position 1 should be used for a doorstrike, electrified handleset,  or other fail-secure device.  Position 2 would be used for a maglock or other fail-safe device.

If the output is operating backwards from what is expected but the LED is indicating correctly with relation to the input, the white jumper should be changed.

Red Jumper

The red jumper sets the FAI activation of the zone.  Position 1 enables FAI activation, while position 2 deactivates FAI for the zone.  The setting of the blue jumper is crucial to proper FAI operation.  Remember that the LED for the zone should flash when the door is unlocked.  If the blue jumper is set incorrectly, the LED will be flashing when the door is locked.  This presents a problem when an FAI activation is received because the C8 thinks the door is already unlocked, so the output does not change.  If the LED is operating backwards from what is intended, move the Blue and White jumpers to the opposite position that they are currently in and FAI should begin working properly.

Settings Chart

The manual for the C8 board has a very helpful chart for jumper settings.  The Common Jumper Settings chart is organized by output type.  Find the desired output type, then look down to find the desired input type.  Then select With or without FAI and look across the row for the jumper settings for that configuration.  This chart covers 99 percent of common applications.


Next part we will cover the usage of our Excel-based C8 Jumper Configuration Tool for help with jumper settings.  Until then, if you need any assistance, our Technical Support department is here to help.