The JNIOR has Dry Contact Relays. Dry contact relays must have power supplied from an external source.
The relays can be set for Normally open or Normally Closed operation. They are normally open when manufactured.
Controlling the relay is the same regardless of the mode that they are in. Switching the relay to Normally Closed basically causes the relay to be inverted. When you command the relay to close it will open. Sounds backward right? By commanding the relay to close you are basically energizing the relay. Energizing the relay puts it in the opposite state of its normal condition. Normally Opened relays will Close and Normally Closed relays will Open.
There are internal jumpers that allow you to change the operation of some of the internal relays depending on the model. On the Model 410 and Model 414, output channels 1 and 2 have jumpers to select the mode of operation. The Model 412 and Model 412 DMX have outputs channels 1, 2, 9, and 10 that can be either Normally Open or Normally Closed.
To change the relay from Normally Open to Normally Closed you need to open the JNIOR and move the factory-supplied JNIOR from the outermost pins (as shown on the upper jumper) to the innermost pins (as shown on the lower jumper).
The Power 4 Relay Output Module has both the Normally Open and Normally Closed pins available on the connector. There is no need to move a jumper.