Set this parameter equal to the name of the amplitude curve that defines the magnitude of the distributed electric charge during the step. If this parameter is omitted, the reference magnitude is applied immediately at the beginning of the step or linearly over the step, depending on the value assigned to the AMPLITUDE parameter on the STEP option (Defining an Analysis).
OP
Set OP=MOD (default) for existing DSECHARGEs to remain, with this option defining electric charges to be added or modified. Set OP=NEW if all existing DSECHARGEs applied to the model should be removed.
Optional, mutually exclusive parameters for matrix generation and direct-solution, steady-state dynamics analysis
IMAGINARY
Include this parameter to define the imaginary (out-of-phase) part of the loading.
REAL
Include this parameter (default) to define the real (in-phase) part of the loading.
Data lines to define distributed electric charges
First line
Surface name.
Distributed electric charge label ES.
Reference electric surface charge magnitude. (Units of CL−2.)
Repeat this data line as often as necessary to define distributed electric charges for various surfaces.