These are the pins of the optocoupler output transistors and they can be connected quite freely, as long as something limits the current to a safe value.
You can connect the "-" outputs to ground and the "+" outputs to the inputs that respond to a short circuit to ground, or connect the "+" outputs to the plus of the power supply (no more than 24V) and the "-" outputs to the inputs that respond to positive voltage.
Additionally, these outputs can be connected both in series and in parallel.
For example, the outputs of several ALM controllers in parallel (activation of any one will change the state) and PEND in series (activation of all of them will change the state).