Published in Blog

Understanding the C8 Board - Part 3 - Outputs Featured

Friday, 18 September 2015 11:33 Written by 

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

Part 1 - Power and LEDs
Part 2 - Inputs

This week we will go in-depth on the outputs of the C8, including the wiring, operation, and jumper configuration.

The Anatomy of the C8 Output

Like the inputs, each output of the C8 has two terminals, labeled A and B.  Each output may be individually configured for a voltage output or a relay output and contains a reverse diode to dissipate and reverse EMF from a locking device or other inductive load.  See our White Paper and Application note on reverse EMF for more information.

When configured as a voltage output, the B terminal is the positive and the A terminal is the DC Common (ground).

C4

C8 Voltage Output

When configured as a relay output, due to the reverse diode, the current must be fed through the contact in the proper direction.  Regardless of what the relay output is activating, there will be a current present.  If the relay output of the C8 is connected backwards, the reverse diode will always be conducting and will not change with the relay.

C1

C8 Relay Output

Each output has four configuration jumpers, detailed below.

Black Jumpers (C and E)

The black jumpers for each zone, labeled C and E, configure the output for either a voltage output or a relay output.  BOTH jumpers must always be set in the same position (by the jumpers' markings) for proper operation.  Check the position markings carefully on the PC board, as position 1 and 2 for each of the black jumpers is different.

By setting the black jumpers in position 1, the output will be configured for a relay output.  By setting these jumpers to position 2, the output will be configured as a voltage output.

White Jumper (F)

The white jumper selects between the NO and NC of the output relay.  When set for a relay output, this selects a NO or NC output.  When set for a voltage output, this selects whether the output is normally powered or not powered (maglock or doorstrike). 

By setting the white jumper in position 1, the output will be NO or will normally have no voltage on the output until the input is activated (flashing green LED).  This is the typical setting for a fail-secure door strike or electrified handleset.

By setting the white jumper in position 2, the output will be NC or will normally have voltage present on the output until the input is activated.  This is the typical setting for a fail-safe maglock.

Again, there is no need to memorize all of the settings - once the blue jumper for the input is set properly (steady when locked, flashing when unlocked - see Part 2), the white jumper can be changed until the output operates correctly.

Yellow Jumper (D)

The yellow jumper selects between the buss 1 and buss 2 voltage supplied to the C8 for each output (See Part 1).  If only a single voltage source is connected to the C8, then this jumper should remain in position 1.  If two power sources are connected to the C8, then setting this jumper in position 1 will select the voltage source connected to B1 and position 2 will select the B2 power source.

Note that this jumper has no effect when the output is set as a relay output.

Voltage Output

The most common output configuration for a C8 is a voltage output.  When connecting a device to the terminals when set as a voltage output, the positive connection goes to the B terminal and the negative connection goes to the A terminal.

C2

C8 Voltage Output Wiring

Relay Output

When configured as a relay output, the current through the relay must flow from the B terminal to the A terminal (the more positive side of the voltage on the B terminal).  Note that ONLY a DC voltage may be switched through the C8 relay due to the reverse polarity diode.

C3

C8 Relay Output Wiring

Next Week

Next week we will go into detail on the jumper settings of the C8, including the usage of our Excel-based C8 Jumper Configuration Tool.  Until then, if you need any assistance, our This e-mail address is being protected from spambots. You need JavaScript enabled to view it department is here to help.

Read 2303 times
Rate this item
(0 votes)
Mike

LifeSafety Power Technical Support and Applications
mbone@lifesafetypower.com
(
888)577-2898 x203

Website: www.lifesafetypower.com