GE M60 Instruction Manual

Also see for M60: Communications manual Communications guide Instruction manual Instruction manual

Contents

5-106 M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUALPRODUCT SETUP CHAPTER 5: SETTINGS5The configuration menu allows a maximum of four ASDUs containing measurands.Measurands are sent as a response to Class 2 requests, which are cyclic requests coming from the master.TYPE IDENTIFICATION (TYP) — The configuration field TYP indicates how many measurands are present in the correspondingASDU. Each ASDU can take either 4 or 9 measurands maximum, depending on the type identification (3 respectively 9). Forany change to take effect, restart the relay.FUNCTION TYPE (FUN) and INFORMATION NUMBER (INF) — These two fields form the Information Object Identifier of the ASDUas defined in IEC 60870-103. For any change to take effect, restart the relay.SCAN TIMEOUT (SCAN TOUT) — This is the cyclic period used by the M60 to decide when a measurand ASDU is included in aresponse. The measurand is sent as response to a Class 2 request when the corresponding timeout expires. The defaultvalue 0 means 500 ms.ANALOG # — This field contains the actual measurand to be sent in the response to the master. The measurands can bemapped using elements from a list of FlexAnalog operands. The measurands sent are voltage, current, power, powerfactor, and frequency. If any other FlexAnalog is chosen, the M60 sends 0 instead of its value. Note that the power istransmitted in KW, not W. Measurands are transmitted as ASDU 3 or ASDU 9 (type identification value set to measurands I,respectively measurands II).Each IEC 60870-5-103 measurands list ends at the first unconfigured ("Off") value. Any measurand assigned after the first"Off" value is ignored.At least one measurand per ASDU must be configured in order to configure the following ASDU. For example, the user canconfigure only one measurand for each ASDU, but the user is not allowed to skip ASDU 2 and configure measurands inASDU 3.For any change to take effect, restart the relay.ANALOG # FACTOR and OFFSET — For each measurand included in the ASDU, a factor and offset also can be configured. Thefactor and offset allow for scaling to be performed on measurands. The final measurement sent to the IEC 60870-103master is then "a*x + b," where x is the measurand, a is the multiplying factor and b is the offset. The master has to performthe reversed operation in order to retrieve the actual value if such scaling is done. By default a = 1 and b = 0, so no scalingis done if these values are left at their defaults. Examples of when scaling is appropriate are as follows:• If the measured value contains decimals and it is important to preserve the resolution. Since the format fortransmitting the measurand does not permit decimals, a factor a>1 can be applied before transmission. For example,a frequency F=59.9Hz can be transmitted as Ft = 10 * F = 10 * 59.9 = 599. In this case a = 10, b = 0. The master receives599 and has to divide by 10 to retrieve the real value 59.9.• If the measured value is larger than what fits in the format defined in IEC 103. The format defined in the standardallows for signed integers up to 4095. By offsetting, unsigned integers up to 4096 + 4095 = 8191 are supported.Scaling using factors <1 can be required in such cases. The calculation is outlined in the IEC 60870-5-103 chapter ofthe UR Family Communications Guide. Two examples follow, where you decide factors a and b.Example 1: Nominal power Pn = 100 MW = 100000 KW (power is transmitted in KW)Since P can be both positive and negative:Transmitted power Pt = (4095/(Pn*2.4)) * P = (4095/(100000 * 2.4) ) * P= 0.017 * Pa = 0.017b = 0 ASDU 4 ANALOG 1OFFSET: 0Range: -32768 to 32767 in steps of 1 ASDU 4 ANALOG 9OffRange: FlexAnalog parameter ASDU 4 ANALOG 9FACTOR: 1.000Range: 0.000 to 65.535 in steps of 0.001 ASDU 4 ANALOG 9OFFSET: 0Range: -32768 to 32767 in steps of 1