ANSI GROUP CODE DEFINITIONS

The Group Code is combined with the ANSI reason code to demonstrate who has financial responsibility for the amount. PR - Patient Responsibility This shows what amount the beneficiary or his/her supplemental insurer is responsible for. PR amounts, including the deductible and coinsurance, are totaled in the Patient Responsibility field at the end of each claim. If you already collected an amount from a beneficiary for this claim in excess of the Patient Responsibility total prior to receipt of the remittance notice, you are required by law to refund that excess to the beneficiary. CO - Contractual Obligation CO is always used to identify excess amounts for which the law prohibits Medicare payment and absolves the beneficiary of any financial liability, such as participation agreement violation amounts, limiting charge violations, late filing penalties, or amounts for services not considered to be reasonable and necessary. You may not hold a beneficiary financially responsible for any adjustments identified with this group code. OA - Other Adjustment Used when neither PR nor CO applies, such as with the reason code message that indicates the bill is being paid in full. CR - Correction to or Reversal of a prior decision Demonstrates when there is a change to the decision on a previously adjudicated claim, perhaps as result of a subsequent reopening. CR explains the reason for a change and is always used with PR, CO, or OA to show revised information.

Protection functions
ANSI codeName of functionDefinition12OverspeedDetection of rotating machine overspeed14UnderspeedDetection of rotating machine underspeed21Distance protectionImpedance measurement detection21BUnderimpedanceBack-up phase-to-phase short-circuit protection for generators24Flux controlOverfluxing check25Synchro-checkCheck before paralleling two parts of the power system26ThermostatProtection against overloads27UndervoltageProtection for control of voltage sags27DPositive sequence undervoltageProtection of motors against operation with insufficient voltage27RRemanent undervoltageCheck on the disappearance of voltage sustained by rotating machinesafter the power supply is disconnected27TNThird harmonic undervoltageDetection of stator winding insulation earth faults (impedant neutral)32PDirectional active overpowerProtection against active overpower transfer32QDirectional reactive overpowerProtection against reactive overpower transfer37Phase undercurrent3-phase protection against undercurrent37PDirectional active underpowerProtection against active underpower transfer37QDirectional reactive underpowerProtection against reactive underpower transfer38Bearing temperature monitoringProtection against overheating of rotating machine bearings40Field lossProtection of synchronous machines against faults or field loss46Negative sequence / unbalanceProtection against unbalanced phase current47Negative sequence overvoltageNegative sequence voltage protection and detection of reverse rotation of rotating machines48 - 51LRExcessive starting time and locked rotorProtection of motors against starting with overloads or reduced voltage, and for loads that can block49Thermal overloadProtection against overloads49TRTDsProtection against overheating of machine windings50Instantaneous phase overcurrent3-phase protection against short-circuits50BFBreaker failureChecking and protection if the circuit breaker fails to trip after a tripping order50N or 50GInstantaneous earth faultProtection against earth faults: 50N: residual current calculated or measured by 3 CTs50G: residual current measured directly by a single sensor (CT or core balance CT)50VInstantaneous voltage-restrained phase overcurrent3-phase protection against short-circuits with voltage-dependent threshold50/27Inadvertent generator energizationDetection of inadvertent generator energization51Delayed phase overcurrent3-phase protection against overloads and short-circuits51N or 51GDelayed earth faultProtection against earth faults:51N: residual current calculated or measured by 3 CTs51G: residual current measured directly by a single sensor (CT or core balance CT)51VDelayed voltage-restrained phase overcurrent3-phase protection against short-circuits with voltage-dependent threshold59OvervoltageProtection against excessive voltage or sufficient voltage detection59NNeutral voltage displacementInsulation fault protection63PressureDetection of transformer internal faults (gas, pressure)64REFRestricted earth fault differentialEarth fault protection for star-connected 3-phase windings with earthed neutral64G100% generator stator earth faultDetection of stator winding insulation earth faults (impedant neutral power systems)66Successive startsProtection function that monitors the number of motor starts67Directional phase overcurrent3-phase short-circuit protection according to current flow direction67N/67NCDirectional earth faultEarth fault protection depending on current flow direction (NC: Neutral compensated)78Vector shiftVector shift disconnection protection78PSPole slipDetection of loss of synchronization of synchronous machines79RecloserAutomated device that recloses the circuit breaker after transient line fault tripping81HOverfrequencyProtection against abnormally high frequency81LUnderfrequencyProtection against abnormally low frequency81RRate of change of frequency (ROCOF)Protection for fast disconnection of two parts of the power system87BBusbar differential3-phase protection against busbar internal faults87GGenerator differential3-phase protection against internal faults in AC generators87LLine differential3-phase protection against line internal faults87MMotor differential3-phase protection against internal faults in motors87TTransformer differential3-phase protection against internal faults in transformers
 

ANSI Standard Device Numbers & Common Acronyms