Whether you are performing regular schedule maintenance on the system or in the event of an unexpected system malfunction, the power to the load can be safely transferred without being interrupted. Because some loads are extremely critical and inconvenient to shutdown, a manual transfer of power sources without physically disconnecting the power to the load is ideal. The Manual Bypass Switch is available in 19” or 23” rack mounted panels or in wall mounted enclosures. La Marche offers two types of MBS configurations, a Make-Before-Break (MB4B) and a Break-Before-Make (BB4M). The MB4B switch links both primary and secondary sources momentarily before completing the transfer. The MB4B is the preferred configuration for use with critical loads.