Which Output Tap should be used when connecting to a WCS series power supply


Remove all power from all devices before removing any covers or doors of the system. Disconnect the power at the device and at the power source.


The resolution of this article has many complex steps that may result in unforeseen results if not performed correctly. If you are at all unfamiliar with the requirements, please contact Product Support Services for assistance.


The WCS Series consists of multi-output 24 VAC outdoor power supplies. These power supplies provide output for one to four cameras (depending on the dome or pan and tilt) from a single source. To compensate for voltage losses over long wire runs, 28 VAC outputs are also available

Product Line

Pelco Transmission & Power


  • WCS1-4
  • WCS4-20
  • WCS4-20B


Installation and Service


WARNING: Under light load conditions and high power line input voltage from the utility company, output voltage from the power supply (28 VAC taps only) may reach 32 VAC. This voltage can cause over-voltage damage on 24 VAC devices. Keep in mind that certain devices produce variable loads, including heaters, blowers, and pan and tilt motion; during operation, minimum voltage requirements may create a light load condition that could cause excessive voltage. Therefore, Pelco recommends using a 28 VAC tap only when the supplied wire size for the given load causes an unacceptable output voltage on the 24 VAC tap. Refer to Table D on page 8 to determine acceptable situations for the 28 VAC tap.

Perform the following steps to attach 24 VAC devices to the WCS Series Power Supply:

1. Determine the output connection current draw needed for your devices. Be sure the correct gauge of power wire is used for the distance to the device.

2. For the proper terminal strip connection the voltage range at the device should not exceed 27 VAC.

3. For each device, attach one output wire to the common terminal. Attach the second wire to the appropriate 24 VAC, (26VAC WCS1-4), or 28 VAC terminal.

4. When you finish the wiring connections, double-check the installation for safety purposes.

5. Power up the unit with the on/off switch.

6. Use a voltmeter to verify that used outputs are at appropriate voltage levels.

7. Close the lid and secure it using the latch and screw


Related Topics:

How Do I Connect Power to the WCS1-4