The QM5 has 5 modular “slots”, the QM7, 7 slots and the QM8, 8 slots where the output modules are positioned. Output modules are between one and four slots wide, depending on the output power. An option card position is also available with a choice of standby voltages, remote on/off inhibit or enable, warning signals and a PMBus communications interface. The output modules signals are included as standard.