National Instruments SLSC-12251 User manual

USER MANUAL
SLSC-12251 and SLSC-12252
Fault Insertion Unit, 16 CH, 8 Amps and 8 CH, 30 Amps
SLSC-12251
16 Ch FIU
100 Vpk, 8 Arms MAX
J1: DUT (0-15) J2: LOAD (0-15)
SLSC-12252
8 Ch FIU
100 Vpk, 30 Arms MAX
J1: DUT (0-7) J2: LOAD (0-7)
Contents
Overview...................................................................................................................................2
Safety Guidelines...................................................................................................................... 3
Safety Voltages..................................................................................................................3
EMC Guidelines........................................................................................................................4
Environmental Characteristics.................................................................................................. 4
Installing the SLSC-12251/12252 and RTI-12306................................................................... 5
Getting Started with Software...................................................................................................6

I/O Organization........................................................................................................................6
Properties.................................................................................................................................. 8
Fault Monitoring and Identification........................................................................................ 11
Measuring the Current............................................................................................................ 12
Measuring the Temperature.....................................................................................................12
Switch Control........................................................................................................................ 13
Calibration...............................................................................................................................13
Driving Inductive Loads......................................................................................................... 14
Pinouts.....................................................................................................................................16
Accessories..............................................................................................................................18
RTI-12306....................................................................................................................... 18
Terminal Blocks.............................................................................................................. 19
Overview
This document contains information about the SLSC-12251 (16 channel, 8 amperes) and
SLSC-12252 (8 channel, 30 amperes) Fault Insertion Units (FIU). The SLSC-12251 and
SLSC-12252 are switch matrices with current monitoring, which allows for connections from
each channel to any of the following: Bus A, Bus B, a load, or a paired channel. These devices
also provide a voltage that is proportional to the current through the channel. This voltage can
be measured with another device.
Driver Support
Earliest driver support version for the SLSC-12251 and SLSC-12252.
Table 1. SLSC-12251 and SLSC-12252 Driver Support
Driver Earliest Version Support
NI-SLSC 18.5
Cables and Accessories
The following table lists cables and accessories available for your SLSC device. For a
complete list of accessories and ordering information, refer to ni.com.
Table 2. SLSC-12251 and SLSC-12252 Cables and Accessories
Cable/Accessory Compatibility Part Number
RTI-12306 SLSC-12251 and SLSC-12252 785378-01
TB-12396 SLSC-12251 786640-01
TB-12397 SLSC-12251 (<33 Vdc) 786639-01
TB-12398 SLSC-12252 786638-01
2| ni.com | SLSC-12251 and SLSC-12252 User Manual

Table 2. SLSC-12251 and SLSC-12252 Cables and Accessories (Continued)
Cable/Accessory Compatibility Part Number
TB-12399 SLSC-12252 (<33 Vdc) 786446-01
SP18M-SP18F Cable SLSC-12251 147945-01
SP8M-SP8F Cable SLSC-12252 148299-01
Safety Guidelines
Caution Observe all instructions and cautions in the user documentation. Using
the model in a manner not specified can damage the model and compromise the
built-in safety protection. Return damaged models to NI for repair.
Safety Voltages
Connect only voltages that are below these limits.
Channel-to-channel isolation
Continuous working voltage1100 V peak
Channel-to-earth isolation
Continuous working voltage 100 V peak
Transient overvoltage2920 V peak
Caution If you are using the SLSC-12251/12252 with voltages greater than 60
Vdc, the SLSC chassis must be made touch safe by panel mounting it in a closed
rack to prevent user access to the rear of the device.
These test and measurement circuits are rated for measurements performed on circuits not
directly connected to the electrical distribution system referred to as MAINS.
MAINS is a hazardous live electrical supply system to which equipment is designed to be
connected to for the purpose of powering equipment. This product is rated for measurements
of voltages from specially protected secondary circuits. Such voltage measurements include
signal levels, special equipment, limited-energy parts of equipment, circuits powered by
regulated low-voltage sources, and electronics.
1Working voltage rating is the highest RMS value of the AC or DC voltage across the insulation that
can continuously occur when the equipment is supplied at rated voltage.
2The short duration overvoltage of a few milliseconds or less, oscillatory or non-oscillatory, usually
highly damped.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 3

EMC Guidelines
This product was tested and complies with the regulatory requirements and limits for
electromagnetic compatibility (EMC) stated in the product specifications. These requirements
and limits provide reasonable protection against harmful interference when the product is
operated in the intended operational electromagnetic environment.
This product is intended for use in industrial locations. However, harmful interference may
occur in some installations, when the product is connected to a peripheral device or test object,
or if the product is used in residential or commercial areas. To minimize interference with
radio and television reception and prevent unacceptable performance degradation, install and
use this product in strict accordance with the instructions in the product documentation.
Furthermore, any changes or modifications to the product not expressly approved by National
Instruments could void your authority to operate it under your local regulatory rules.
Notice To ensure the specified EMC performance, operate this product only with
shielded cables and accessories.
Notice To ensure the specified EMC performance, the length of all I/O cables must
be no longer than 3 m (10 ft).
Environmental Characteristics
Temperature and Humidity
Operating temperature 0 °C to 40 °C3
Storage temperature range -40 °C to 85 °C
Operating relative humidity range 10% to 90%, noncondensing
Storage relative humidity range 5% to 95%, noncondensing
Pollution Degree 2
Maximum altitude 2,000 m (800 mbar) (at 25 °C ambient)
Shock and Vibration
Operating shock 30 g peak, half-sine, 11 ms pulse
Operating vibration, random 5 Hz to 500 Hz, 0.3 grms
Non-operating vibration, random 5 Hz to 500 Hz, 2.4 grms
3The chassis internal ambient temperature may reach 85 °C with all slots at the maximum allowed
power dissipation. In the SLSC-12001 chassis this corresponds to an external ambient of 40 °C.
4| ni.com | SLSC-12251 and SLSC-12252 User Manual

Installing the SLSC-12251/12252 and
RTI-12306
Figure 1. Installing the RTI-12306 into the SLSC Chassis
Caution Do not touch the contacts or remove the I/O boards or cables while the
system is energized.
Note Install the SLSC-12251/12252 module and its corresponding RTI-12306 in
the chassis at the same time to ensure proper mating alignment. Complete the
following procedure to ensure proper installation of the module and RTI-12306.
1. Power off the main DC power source or disconnect the power source from the chassis
before installing any modules or RTIs.
2. Ensure that the chassis is powered off. The POWER LED should be off. If the POWER
LED is not off, do not proceed until it is off.
Notice The SLSC chassis and the SLSC-12251/12252 do not support hot
plug-in. The entire chassis must be powered off when a module is inserted or
removed.
3. Loosen the screws on the upper rear panel of the chassis.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 5

4. Position the RTI-12306 at the desired slot and insert the securing screws, but do not fully
tighten them.
5. Insert an SLSC-12251/12252 module into the same slot as its corresponding RTI-12306
while firmly holding the RTI-12306 in place until the RTI-12306 is firmly connected to
the module.
6. Repeat steps 4 and 5 for all required RTIs.
7. Fully tighten the screws for all RTIs and the upper rear panel of the chassis.
Note Waiting until all RTIs and modules are installed to fully tighten the
screws ensures proper alignment for future connections between modules and
RTIs.
8. Fully tighten the two module mounting screws on each newly installed module.
9. Power on the SLSC chassis.
Getting Started with Software
Use the following three examples to familiarize yourself with the NI-SLSC API. These
examples can be found at file path <LabVIEW installation path>\examples\SLSC
\Example Modules\4 or in Example Finder: Example Finder>>SLSC>>NI
Module Examples.
SLSC-12251 & 12252 FIU Module Configuration.vi
This VI demonstrates how to use the NI-SLSC API to configure the switches of the
SLSC-12251 and SLSC-12252 FIU modules.
SLSC-12251 & 12252 FIU Module Fault Monitor.vi
This VI demonstrates how to use the NI-SLSC API to find specific fault locations on the
SLSC-12251 and SLSC-12252 FIU modules when a fault occurs.
SLSC-12251 & 12252 FIU Module Current Sensing.vi
Use this conceptual example to integrate current sensing functionality into your own system.
Note To use this VI you must connect a voltage measurement device to the RTI
that is attached to the module.
I/O Organization
DUT connector J1 is the input connection to each channel. LOAD connector J2 is the output
connection to each channel. Bus A and Bus B are common connections available to all
channels through the RTI-12306.
4A common installation path for the 32-bit version of LabVIEW is C:\Program Files
(x86)\National Instruments\LabVIEW xxxx\examples\SLSC\Example Modules
\.
6| ni.com | SLSC-12251 and SLSC-12252 User Manual

Each switch is organized into two physical channels, Channel_n and ChannelPair_n, where the
range of n is defined in the following table.
Table 3. Range of Channel Index n
Physical Channel Connections SLSC-12251 SLSC-12252
Channel_n DUTn to LOADn, Bus A, or Bus B 0:15 0:7
ChannelPair_n DUTn to DUTn+1, where n is even 0:7 0:3
Figure 2. Channel Connection Pairs
Current Sense (to RTI)
A
DUT n
(0, 2, 4, 6...)
Current Sense (to RTI)
A
DUT n + 1
(1, 3, 5, 7...)
LOAD n
LOAD n + 1
Bus BBus A
Note All switches are open during power-up and after the module is reset.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 7

Properties
Table 4. Fault Monitoring Properties
Property Name Data
Type
Property
Type
Description
NI.FIU.BoardFault Boolean Device True when there is any
fault on the board.
NI.FIU.BoardFault.
BoardOverTemperature
UInt32 Device Starting with the LSB,
each bit represents one of
the board's 4 quadrant
digital temperature
sensors, true when that
sensor exceeds the high
temperature digital
setpoint.
NI.FIU.BoardFault.
OverTemperatureOnChannel
UInt32 Device Starting with the LSB,
each bit represents a
channel, true when that
channel's analog
temperature sensors
exceed the high
temperature analog
transition range.
NI.FIU.BoardFault.
OverTemperatureOnChannelToChannel
UInt32 Device Starting with the LSB,
each bit represents a
channel pair, true when
that channel pair's analog
temperature sensor
exceeds the high
temperature analog
transition range.
NI.FIU.BoardFault.OvercurrentOnBusA Boolean Device True when Bus A
exceeds the Bus High
Current Limit for longer
than its delay time.
NI.FIU.BoardFault.OvercurrentOnBusB Boolean Device True when Bus B
exceeds the Bus High
Current Limit for longer
than its delay time.
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Table 4. Fault Monitoring Properties (Continued)
Property Name Data
Type
Property
Type
Description
NI.FIU.BoardFault.OvercurrentHigh UInt32 Device Starting with the LSB,
each bit represents a
DUT channel, true when
that DUT channel
exceeds the DUT High
Current Limit for longer
than its delay time.
NI.FIU.BoardFault.OvercurrentLow UInt32 Device Starting with the LSB,
each bit represents a
DUT channel, true when
that DUT channel
exceeds the DUT Low
Current Limit for longer
than its delay time.
Table 5. Measurement Properties
Property Name Data
Type
Property
Type
Description
NI.FIU.Calibration.Date Double Device Time, in seconds elapsed
since 12:00 a.m., Friday,
January 1, 1904, Universal
Time, of the last calibration
date of the device.
NI.FIU.Calibration.ExpirationDate Double Device Time, in seconds elapsed
since 12:00 a.m., Friday,
January 1, 1904, Universal
Time, the next recommended
calibration date of the device.
NI.FIU.CurrentTransducer.Gain Double Physical
Channel:
Channel_n
The gain used to calculate the
current from the current
transducer, based on the
voltage input.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 9

Table 5. Measurement Properties (Continued)
Property Name Data
Type
Property
Type
Description
NI.FIU.CurrentTransducer.Offset Double Physical
Channel:
Channel_n
The offset used to calculate
the current from the current
transducer, based on the
voltage input.
NI.FIU.TemperatureSensorN Double Device Degrees Celsius of the
board's 4 quadrant digital
temperature sensors (0:3).
Table 6. Switch Control Properties
Property Name Data
Type
Property
Type
Description
NI.FIU.Preset.BusSource Int32,
String
Physical
Channel:
Channel_n
Allows pre-setting DUT channel
connectivity to Bus A, Bus B or none.
An Update command is required for the
change to take place.
Enumeration:
0 : "NoBus" :
Channel is not connected to any Bus
1 : "BusA" :
Channel is connected to Bus A
2 : "BusB" :
Channel is connected to Bus B
NI.FIU.Preset.InterChannel Int32,
String
Physical
Channel:
ChannelPair_n
Allows pre-setting DUT channel
connection to its partner channel. An
Update command is required for the
change to take place.
Enumeration:
0 : "IndependentChannels" :
Channel n is not connected to n + 1
1 : "ConnectedChannels" :
Channel n is connected to n + 1
10 | ni.com | SLSC-12251 and SLSC-12252 User Manual

Table 6. Switch Control Properties (Continued)
Property Name Data
Type
Property
Type
Description
NI.FIU.Preset.Load Int32,
String
Physical
Channel:
Channel_n
Allows pre-setting DUT channel
connectivity to its load. An Update
command is required for the change to
take place.
Enumeration:
0 : "NoLoad" :
Channel is not connected to its Load
1 : "Load" :
Channel is connected to its Load
NI.FIU.Update N/A Command Executing this command allows the
channel to change to the preset values.
NI.FIU.State.BusSource Int32,
String
Physical
Channel:
Channel_n
Read-only property that represents the
actual connection states for a channel.
See Preset property for enumeration.
NI.FIU.State.InterChannel Int32,
String
Physical
Channel:
ChannelPair_n
Read-only property that represents the
actual connection states for a channel
pair. See Preset property for
enumeration.
NI.FIU.State.Load Int32,
String
Physical
Channel:
Channel_n
Read-only property that represents the
actual connection states for a channel.
See Preset property for enumeration.
Table 7. Version Control Property
Property Name Data Type Property Type Description
NI.FIU.ModuleControllerVersion UInt32 Device Read only Module
Controller Version number.
Fault Monitoring and Identification
The module continuously senses the current and temperature throughout the channels of the
board. If any current or temperature exceeds the specified limits, a fault is declared and the
NI.FIU.BoardFault Boolean property is set to true. When a fault is detected, all switches
are opened, which stops all current and prevents damage to the module. The module must be
reset to clear the fault condition. Any attempt to change a switch's state after a fault will error
out if the module is not reset first.
Poll the NI.FIU.BoardFault property during normal operation to check if a fault
condition exists.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 11

After a fault condition occurs, when the NI.FIU.BoardFault property is true, you can
identify the specific fault condition by reading the NI.FIU.BoardFault.* properties.
Note Values for fault currents, duration, and temperature limits can be found in the
SLSC-12251 Specifications and SLSC-12252 Specifications.
Measuring the Current
Uncalibrated differential voltage signals that are proportional to the DUT channel's current are
available on the RTI-12306 connector, which allows the signals to be measured by another
device. The external voltage measurement can be used with each channel's stored gain and
offset coefficients to calculate the calibrated current as follows:
I(Amps) = NI.FIU.CurrentTransducer.Gain × Vmeasured+
NI.FIU.CurrentTransducer.Offset
where NI.FIU.CurrentTransducer.Gain and
NI.FIU.CurrentTransducer.Offset are properties of Channel_n.
Note It is important to use the corresponding channel offset and gain for the
current sensors because the values are adjusted to meet the specified accuracy.
Measuring the Temperature
The module's four digital temperature sensors measure the temperature conditions in the
board. For temperature measurement, read the NI.FIU.TemperatureSensorN property
where N = 0,1,2,3.
The physical locations of the temperature sensors are as follows:
Figure 3. Temperature Sensor Locations on SLSC-12251 and SLSC-12252 Boards
01
23
12 | ni.com | SLSC-12251 and SLSC-12252 User Manual

Switch Control
Change the state of a switch by completing the following steps:
1. Preset the new state of the switch by setting the NI.FIU.Preset* properties for each
physical channel Channel_n and ChannelPair_n. There is no limit to the number of
preset switch states that can be written, but subsequent writes to the same physical switch
will overwrite any previous values.
2. After completing all preset writes, update the switch state with the NI.FIU.Update
command.
3. The device will transition the switch states in the following sequence, starting at t = 0 ms
upon execution of the NI.FIU.Update command.
t = 0.12 ms Connect LOADs to DUTs
t = 0.32 ms Disconnect DUTs from BusA/B and pair channels
t = 0.52 ms Connect DUTs to BusA/B and pair channels
t = 0.72 ms Disconnect LOADs from DUTs
4. The current state of the switch can be confirmed by reading the NI.FIU.State.*
properties.
Modifying the NI.FIU.Preset* properties will not change the state of the switch. A switch
transition on the pending preset values is only triggered upon execution of the
NI.FIU.Update command. This allows concurrent switch operations in different physical
channels.
Calibration
The factory calibration values for each channel's gain and offset coefficients may be
overwritten by the user. NI recommends calibrating the board under the following conditions:
1. Power on the module for at least one hour. Ensure that normal air flow is unblocked
around the SLSC chassis. Leave at least one switch closed during this time. Validate that
the switch is closed by reading back the NI.FIU.State.* properties, which ensures the
board is operating as expected.
2. Use one of the below paths to calibrate the device:
• DUTn to Bus A
• DUTn to Bus B
• DUTn to LOADn
3. Close the chosen channel and provide a known DC current through that path.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 13

4. Record the applied current value and the corresponding differential voltage output for that
channel.
Note Averaging data in multiples of 0.1 seconds helps remove 50 Hz or 60 Hz
noise.
5. Repeat the previous step at five or more DC current points from ±8 A on the SLSC-12251
and ±30 A on the SLSC-12252.
6. Repeat Step 3 and Step 4 for all channels.
7. Use the data for a least squares fit to determine the gain and offset coefficients.
8. Read back and save the capabilities section of the Non-Volatile Memory (NVMEM).
9. Modify the saved data in the following ways:
a. Update the NI.FIU.CurrentTransducer.Offset and
NI.FIU.CurrentTransducer.Gain property values of each channel for which
the calibration values were measured.
b. Use the "Get Time/Date in Seconds" VI to generate the timestamp in double format
to write to the NI.FIU.Calibration.Date property.
c. Add the number of seconds of the calibration interval to the timestamp to generate
the value to write to the NI.FIU.Calibration.ExpirationDate property.
10. Write the modified data back to the capabilities section of the device's NVMEM. Use the
device's serial number and the password ni to write this section.
Driving Inductive Loads
When a channel is providing current to an inductive load and the current is interrupted by
opening the switch, the inductor voltage rapidly increases due to Vinductor = L di/dt. This
inductive kickback, or flyback voltage, is usually limited by placing a catch diode across the
inductor. If a catch diode is not used, the FET switch will enter Avalanche breakdown.
Avalanche breakdown occurs when the flyback voltage exceeds approximately 120% of its
rated breakdown voltage V(BR)DSS.
When using an inductive load with no catch diode, it is possible to generate voltages on the
LOAD terminals in excess of 120 V, even if a non-hazardous voltage level is driving the
inductor.
In addition to the hazard of generating high voltages in a low voltage system, Avalanche
breakdown operation is also limited by the energy dissipation available per switch event.
Note Refer to the SLSC-12251 Specifications and SLSC-12252 Specifications for
specific values related to Avalanche breakdown operation.
This energy is lower than the 25 °C specifications rating of the FET because the SLSC chassis
can reach internal temperatures of up to 85 °C. Using this energy rating and the Avalanche test
current IAV of 150 A from the FET datasheet, the test inductance used to determine the
Avalanche characteristics can be found using the following equation:
14 | ni.com | SLSC-12251 and SLSC-12252 User Manual

EAS =1
2L×IAS
2
where EAS = 300 mJ and IAS = 150 A, giving L = 0.0267 mH.
The temperature rise in the FET switch is given from the following equation:
ΔTM=F2×i0
3
2×L
1
2
where F2 is a constant, and i(0) is the initial inductor current.
Use this equation once for the datasheet test case where I = 150 A and L = 0.0267 mH. Use
this equation again for the inductor and max current used on the actual load. By equating the
temperature rise for these two use cases, the constant F2 cancels, and the maximum current for
a given load inductance can be determined using the following equation:
ILMAX = 150A×0.0267mH
LLoad
1
3
where LLOAD is in mH.
For example, ILMAX = 9.65 A with a 100 mH inductor. The FET switch will be damaged if
more than this current is actively interrupted while driving this inductor.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 15

Pinouts
Figure 4. SLSC-12251 Pinout
SLSC-12251
16 Ch FIU
100 Vpk, 8 Arms MAX
J1: DUT (0-15) J2: LOAD (0-15)
E4
1 2 3
4 5 6
E4 E4
7 8 9
10 11 12
E4E4
1 2 3
4 5 6
E4 E4 E4 E4E5
1 2 3
1 2 3
4 5 6
4 5 6
7 8 9
10 11 12
Ch3_DUT
Ch2_DUT
Ch4_DUT
Ch5_DUT
Ch1_DUT
Ch0_DUT
Ch6_DUT
Ch7_DUTNC
NC
Ch15_DUT
Ch14_DUT
Ch8_DUT
Ch9_DUT
Ch10_DUT
Ch11_DUT
Ch12_DUT
Ch13_DUT
Ch12_LOAD
Ch13_LOAD
Ch11_LOAD
Ch10_LOAD
Ch14_LOAD
Ch15_LOAD
Ch9_LOAD
Ch8_LOADNC
NC
Ch0_LOAD
Ch1_LOAD
Ch7_LOAD
Ch6_LOAD
Ch5_LOAD
Ch4_LOAD
Ch3_LOAD
Ch2_LOAD
Note The input to each channel is Chx_DUT. The output to each channel is
Chx_LOAD. NC indicates not connected and should not be used.
.
16 | ni.com | SLSC-12251 and SLSC-12252 User Manual

Figure 5. SLSC-12252 Pinout
SLSC-12252
8 Ch FIU
100 Vpk, 30 Arms MAX
J1: DUT (0-7) J2: LOAD (0-7)
4
Ch1_DUT
Ch3_DUT
Ch4_DUT
Ch6_DUT
Ch0_DUT
Ch2_DUT
Ch5_DUT
Ch7_DUT
Ch6_LOAD
Ch4_LOAD
Ch3_LOAD
Ch1_LOAD
Ch7_LOAD
Ch5_LOAD
Ch2_LOAD
Ch0_LOAD
4 4
C4 C4C3
2 2
3 3 1 1
4
C4
22
3 31 1
C4 C3
Note The input to each channel is Chx_DUT. The output to each channel is
Chx_LOAD. NC indicates not connected and should not be used.
.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 17

Accessories
RTI-12306
The RTI-12306 is the required rear transition interface for use with SLSC-12251 and
SLSC-12252 devices. The RTI-12306 provides connections to Bus A, Bus B, and all current
sensor outputs through the MDR connectors.
RTI-12306 Front View
Figure 6. RTI-12306 Front View
J4, Bus A
J5, Bus B
MDR J2
CH(0-7)
MDR J3
CH(8-15)
RTI-12306 Bus Connections
Wire gauge 6 AWG to 18 AWG (NI recommends using a
stranded wire with a ferrule or a solid core
wire.)
Maximum voltage 100 Vpeak
Maximum current 60 Arms
18 | ni.com | SLSC-12251 and SLSC-12252 User Manual

RTI-12306 MDR Pinout
Figure 7. RTI-12306 MDR Pinout
GND
CurrentCh [6]–
CurrentCh [6]+
GND
CurrentCh [4]–
CurrentCh [4]+
GND
CurrentCh [2]–
CurrentCh [2]+
GND
CurrentCh [0]–
CurrentCh [0]+
GND
GND
CurrentCh [7]–
CurrentCh [7]+
GND
CurrentCh [5]–
CurrentCh [5]+
GND
CurrentCh [3]–
CurrentCh [3]+
GND
CurrentCh [1]–
CurrentCh [1]+
GND
13
12
11
10
9
8
7
6
5
4
3
2
1
26
25
24
23
22
21
20
19
18
17
16
15
14
GND
CurrentCh [14]–
CurrentCh [14]+
GND
CurrentCh [12]–
CurrentCh [12]+
GND
CurrentCh [10]–
CurrentCh [10]+
GND
CurrentCh [8]–
CurrentCh [8]+
GND
GND
CurrentCh [15]–
CurrentCh [15]+
GND
CurrentCh [13]–
CurrentCh [13]+
GND
CurrentCh [11]–
CurrentCh [11]+
GND
CurrentCh [9]–
CurrentCh [9]+
GND
13
12
11
10
9
8
7
6
5
4
3
2
1
26
25
24
23
22
21
20
19
18
17
16
15
14
J2 J3
Table 8. RTI-12306 MDR Pinout Signal Descriptions
Signal Description
CurrentCh[n]+ Voltage proportional to current on Channel_n, plus common mode voltage.
The full scale range is ±2 +2.5 V.
CurrentCh[n]– Common mode voltage of Channel_n (2.5 V).
GND Ground reference for all signals.
Terminal Blocks
The following terminal blocks connect to the LOAD connectors on the SLSC-12251/12252
through SPxM-SPxF cables and provide easy spring terminal connections to the LOAD
channels. The low voltage (<33 V) terminal block options also provide an HD44 connection
for routing low current sense LOAD signals to an SLSC-12201 module.
On all terminal blocks, terminal J5 can be used for Chassis Ground, which is tied to the metal
case standoffs and connector jack-sockets. Terminal J6 is DGND, which is the GND reference
of the signals on the HD44 connector.
TB-12396
The TB-12396 is a terminal block for use with SLSC-12251 devices.
SLSC-12251 and SLSC-12252 User Manual | © National Instruments | 19

Figure 8. TB-12396 Front View
CH15 CH14 CH12 CH9CH11CH13 CH10 CH8
CH5 CH6
CH0 CH1 CH3 CH7CH4 CH2
DGND
18
13
16
J1
J2
J3
J5
J6
TB-12397
The TB-12397 is a terminal block for use with the SLSC-12251 when all signals are <33Vdc.
The HD44 connector J4 allows for sense connections (low current only) of the channels to
another device such as the SLSC-12201.
Figure 9. TB-12397 Front View
CH15 CH14 CH12 CH9CH11CH13 CH10 CH8
CH5 CH6
CH0 CH1 CH3 CH7CH4 CH2
DGND
18
13
16
131
15
44
J1
J2
J3
J4
J5
J6
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