16.2.5 SettingsTable 651:SSIMG Group settings (basic)Name Values (Range) Unit Step Default DescriptionOperation OffOn- - Off Operation Off / OnPressAlmLimit 1.00 - 100.00 - 0.01 5.00 Alarm setting for pressurePressLOLimit 1.00 - 100.00 - 0.01 3.00 Pressure lockout settingTempAlarmLimit -40.00 - 200.00 - 0.01 30.00 Temperature alarm level setting of themediumTempLOLimit -40.00 - 200.00 - 0.01 30.00 Temperature lockout level of the mediumtPressureAlarm 0.000 - 60.000 s 0.001 0.000 Time delay for pressure alarmtPressureLO 0.000 - 60.000 s 0.001 0.000 Time delay for pressure lockout indicationtTempAlarm 0.000 - 60.000 s 0.001 0.000 Time delay for temperature alarmtTempLockOut 0.000 - 60.000 s 0.001 0.000 Time delay for temperture lockouttResetPressAlm 0.000 - 60.000 s 0.001 0.000 Reset time delay for pressure alarmtResetPressLO 0.000 - 60.000 s 0.001 0.000 Reset time delay for pressure lockouttResetTempLO 0.000 - 60.000 s 0.001 0.000 Reset time delay for temperture lockouttResetTempAlm 0.000 - 60.000 s 0.001 0.000 Reset time delay for temperture alarm16.2.6 Operation principleGas medium supervision SSIMG is used to monitor the gas pressure in the circuitbreaker. Binary inputs of gas density PRES_ALM, PRES_LO, and gas pressure signalPRESSURE, are taken into account to initiate the alarms PRES_ALM and PRES_LO.When PRESSURE is less than PressAlmLimit or binary signal from CB PRES_ALMis high then the gas pressure alarm, PRES_ALM will be initiated. Similarly, ifpressure input PRESSURE is less than PressLOLimit or binary signal from CBPRES_LO is high or temperature input TEMP is above lockout level TempLOLimitthen the gas pressure lockout, PRES_LO will be initiated.There may be sudden change in pressure of the gas for a very small time, for which thefunction need not to initiate any alarm. That is why two time delays tPressureAlarm ortPressureLO have been included. If the pressure goes below the settings for more thanthese time delays, then only the corresponding alarm PRES_ALM or lockoutPRES_LO will be initiated. The SET_P_LO binary input is used for setting the gaspressure lockout. The PRES_LO output retains the last value until it is reset by usingthe binary input RESET_LO. Hysteresis type comparators have been used with thesetting for relative and absolute hysteresis. The binary input BLK_ALM can be usedto block the alarms, and the BLOCK input can block both alarms and the lockoutindication.Temperature of the medium is available from the input signal of temperature. Thesignal is monitored to detect high temperature.Section 16 1MRK502052-UEN BMonitoring892Technical manual
