constraint_eqn_027 Subroutine

   subroutine constraint_eqn_027(tmp_cc, tmp_con, tmp_err, tmp_symbol, tmp_units)
      !! Equation for Central Solenoid current density upper limit at BOP
      !! author: P B Lloyd, CCFE, Culham Science Centre
      !! args : output structure : residual error; constraint value;
      !! residual error in physical units; output string; units string
      !! Equation for Central Solenoid current density upper limit at BOP
      !! #=# pfcoil
      !! #=#=# fjohc0, j_cs_critical_pulse_start
      !! and hence also optional here.
      !! Logic change during pre-factoring: err, symbol, units will be assigned only if present.
      !! fjohc0 : input real : f-value for central solenoid current at beginning of pulse
      !! j_cs_critical_pulse_start : input real : allowable central solenoid current density at beginning of pulse (A/m2)
      !! j_cs_pulse_start : input real : central solenoid overall current density at beginning of pulse (A/m2)
      use constraint_variables, only: fjohc0
      use pfcoil_variables, only: j_cs_critical_pulse_start, j_cs_pulse_start
      implicit none
            real(dp), intent(out) :: tmp_cc
      real(dp), intent(out) :: tmp_con
      real(dp), intent(out) :: tmp_err
      character(len=1), intent(out) :: tmp_symbol
      character(len=10), intent(out) :: tmp_units

      tmp_cc =  j_cs_pulse_start/j_cs_critical_pulse_start - 1.0D0 * fjohc0
      tmp_con = j_cs_critical_pulse_start
      tmp_err = j_cs_critical_pulse_start - j_cs_pulse_start / fjohc0
      tmp_symbol = '<'
      tmp_units = 'A/m2'

   end subroutine constraint_eqn_027