The Z+ series has extensive safety protection features to prevent damage to expensive equipment. These include locking the front panel controls to avoid accidental adjustment, and a last memory setting to automatically recover the programming functions after the AC has been removed. An option is also provided to have the output remain off or resume normal operation after a power interruption. If the output increases or decreases beyond desired limits, the unit can be programmed to shut down. Likewise, the unit can be shut down if it unexpectedly transitions from constant voltage to constant current mode. After an over temperature condition, the unit can be set to stay off or resume normal operation.