Woodward MSLC-2XT Master Synchronizer and Load Control Process Control

Process Control

≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡

A process controller is provided for cogeneration, fluid level maintenance, pressure control or other ap

plications. An adjustable bandwidth signal input filter, flexible PID controller adjustments, selectable for

direct or indirect action, allow the process control to be used in a wide variety of applications.

An analog signal input (signal variety: 0 to 20mA, 4 to 20mA, 0 to 5V, 1 to 5V and 0 to 10V) provides

the process signal to the MSLC-2. The MSLC-2 includes an internal digital process reference, which

may be controlled by the raise and lower switch contact inputs or by an external analog input signal as

remote process reference. The MSLC-2 also has a Modbus address for process reference control. The

output of the process control, like the import/export control, is the percentage of rated load setpoint to

the individual generators in isochronous load sharing.

An adjustable ramp allows smooth entry and exit from the process control mode. When the process

control mode is selected, the load reference is ramped in a direction to reduce the error between the

process input and the process reference. When the error is minimized or the reference first reaches

either the high or the low specified limits, the process controllers PID loop is activated. When the load

reference output reaches either 100% or 0%, the control will maintain that load reference until process

control is established.

The MSLC-2 is not capable of overloading or reverse powering the generators in an attempt to meet

the process reference. The high and low limit switches mentioned above can be used to indicate that

either too many or too few generators are online to maintain the process within its limits.