Transducer Inputs/Outputs; Dcma Inputs - GE L90 Instruction Manual

CHAPTER 5: SETTINGS
The three sources of commands each activates the
RESET
command also creates its individual operand
the command. Each of these three operands generates an event in the event record when activated. The
setting here selects the operand that activates the

5.10 Transducer inputs/outputs

5.10.1 DCmA inputs

SETTINGS  TRANSDUCER I/O  DCMA INPUTS  DCMA INPUT H1(U8)
 DCMA INPUT H1

The L90 is provided with optional DCmA capability. This feature is specified as an option at the time of ordering.
See the Order Codes section in chapter 2 for details.
Hardware and software are provided to receive signals from external transducers and to convert these signals into a
digital format for use as required. The relay accepts inputs in the range of –1 to +20 mA DC, suitable for use with most
common transducer output ranges; all inputs are assumed to be linear over the complete range. Hardware details are
contained 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 range
and quantity of the external transducer primary input parameter, such as DC voltage or temperature. The relay simplifies
this 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 the
settings 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 general
manner that is used for CTs and VTs. Each channel is assigned a slot letter followed by the row number, 1 through 8
inclusive, 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 channel
of 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. An
alphanumeric "ID" is assigned to each channel; this ID is included in the channel actual value, along with the programmed
units associated with the parameter measured by the transducer, such as volts, °C, megawatts, and so on. This ID is also
used to reference the channel as the input parameter to features designed to measure this type of parameter. The
setting specifies the mA DC range of the transducer connected to the input channel.
INPUT H1 RANGE
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
RESET OP
RESET OP (PUSHBUTTON)
RESET OP (OPERAND)
DCMA INPUT H1

FUNCTION: Disabled
DCMA INPUT H1 ID:

DCMA Ip 1
DCMA INPUT H1

UNITS: μA
DCMA INPUT H1

RANGE: 0 to -1 mA
DCMA INPUT H1 MIN

VALUE: 0.000
DCMA INPUT H1 MAX

VALUE: 0.000
TRANSDUCER INPUTS/OUTPUTS
FlexLogic operand. Each individual source of a
, , or
RESET OP (COMMS) RESET OP (OPERAND)
operand.
Range: Disabled, Enabled
Range: up to 20 alphanumeric characters
Range: six alphanumeric characters
Range: 0 to –1 mA, 0 to +1 mA, –1 to +1 mA, 0 to 5
mA, 0 to 10mA, 0 to 20 mA, 4 to 20 m
Range: –9999.999 to +9999.999 in steps of 0.001
Range: –9999.999 to +9999.999 in steps of 0.001
RESET
to identify the source of
RESET OPERAND
DCMA
5-401
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