CHAPTER 5: SETTINGS TRANSDUCER INPUTS/OUTPUTSD30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL 5-31555.10 Transducer inputs/outputs5.10.1 DCmA inputsSETTINGS TRANSDUCER I/O DCMA INPUTS DCMA INPUT H1(W8)Hardware and software are provided to receive signals from external transducers and to convert these signals into adigital format for use as required. The relay accepts inputs in the range of –1 to +20 mA DC, suitable for use with mostcommon transducer output ranges; all inputs are assumed to be linear over the complete range. Hardware details arecontained in chapter 3.Before the DCmA input signal can be used, the value of the signal measured by the relay must be converted to the rangeand quantity of the external transducer primary input parameter, such as DC voltage or temperature. The relay simplifiesthis process by internally scaling the output from the external transducer and displaying the actual primary parameter.DCmA input channels are arranged in a manner similar to CT and VT channels. Configure the individual channels with thesettings shown here.The channels are arranged in sub-modules of two channels, numbered from 1 through 8 from top to bottom. On power-up,the relay automatically generates configuration settings for every channel, based on the order code, in the same generalmanner that is used for CTs and VTs. Each channel is assigned a slot letter followed by the row number, 1 through 8inclusive, which is used as the channel number. The relay generates an actual value for each available input channel.Settings are generated automatically for every channel available in the specific relay as shown above for the first channelof a type 5F transducer module installed in slot H.The function of the channel can be “Enabled” or “Disabled.” If “Disabled,” no actual values are created for the channel. Analphanumeric “ID” is assigned to each channel; this ID is included in the channel actual value, along with the programmedunits associated with the parameter measured by the transducer, such as volts, °C, megawatts, and so on. This ID is alsoused to reference the channel as the input parameter to features designed to measure this type of parameter. The DCMAINPUT H1 RANGE setting specifies the mA DC range of the transducer connected to the input channel.The DCMA INPUT H1 MIN VALUE and DCMA INPUT H1 MAX VALUE settings are used to program the span of the transducer inprimary units. For example, a temperature transducer might have a span from 0 to 250 °C; in this case the DCMA INPUT H1MIN VALUE value is “0” and the DCMA INPUT H1 MAX VALUE value is “250.” Another example is a watts transducer with a spanfrom –20 to +180 MW; in this case the DCMA INPUT H1 MIN VALUE value is “–20” and the DCMA INPUT H1 MAX VALUE value is“180.” Intermediate values between the minimum and maximum values are scaled linearly. DCMA INPUT H1 DCMA INPUT H1FUNCTION: DisabledRange: Disabled, Enabled DCMA INPUT H1 ID:DCMA Ip 1Range: up to 20 alphanumeric characters DCMA INPUT H1UNITS: μARange: six alphanumeric characters DCMA INPUT H1RANGE: 0 to -1 mARange: 0 to –1 mA, 0 to +1 mA, –1 to +1 mA, 0 to 5mA, 0 to 10mA, 0 to 20 mA, 4 to 20 m DCMA INPUT H1 MINVALUE: 0.000Range: –9999.999 to +9999.999 in steps of 0.001 DCMA INPUT H1 MAXVALUE: 0.000Range: –9999.999 to +9999.999 in steps of 0.001The D30 is provided with optional DCmA capability. This feature is specified as an option at the time ofordering. See the Order Codes section in chapter 2 for details.
