National Instruments TBX-1316 Installation Manual

INSTALLATION GUIDE

TBX-1316 High-Voltage
Attenuator Terminal Block

This guide describes how to install and use the TBX-1316 high-voltage
attenuator terminal block with the following modules:

• SCXI-1125 (recommended)

• SCXI-1126

• SCXI-1120/D

The TBX-1316 is a shielded metal enclosure with a built-in high-voltage
attenuator. You can use it to measure high-voltage signals of up to 1000 V
Category I and 600 V Category II.

Caution Do not use the TBX-1316 to connect to signals above 600 V Category II. Do not

use the TBX-1316 in Category III or IV applications. Do not connect to MAINS supply
circuits above 600 VAC.

The TBX-1316 has eight differential high-voltage input channels. Each
high-voltage input channel has three screw terminals—one each for input
plus, input minus, and chassis ground. For maximum safety, all the
chassis-ground terminals and the enclosure are connected. You can use
6 to 20 AWG signal wire in the screw terminals. Use an SH3232 shielded
cable to connect the TBX-1316 to the module.

Note Refer to the Read Me First: Safety and Radio-Interference document for definitions

of Categories and other safety information.

Caution Do not use uninsulated input signal wires. All input signal wires must be

separated from each other and must have a minimum voltage rating of 1000 V for
Category I or 600 V for Category II and have a temperature rating of 90 °C.

Each input channel is formed by a pair of 200:1 fixed-attenuation-ratio
high-voltage resistor networks. The nominal inaccuracy of the attenuation
factor is < 1%, and the attenuation-ratio drift temperature coefficient is
< 20 ppm/°C.

Caution Install an application appropriate UL-Listed external breaker (disconnect) for

each input line.

A calibration EEPROM is built into the TBX-1316. When the TBX-1316
is used in conjunction with an SCXI-1125, the EEPROM stores calibration
constants. These constants provide software correction values that the
application development software uses to correct measurements for gain
error in the attenuation circuitry. The EEPROM is shipped with nominal
values. Refer to the Calibrating the TBX-1316 section for calibration
information.

Conventions

The following conventions are used in this guide:

» The » symbol leads you through nested menu items and dialog box options

to a final action. The sequence File»Page Setup»Options directs you to
pull down the File menu, select the Page Setup item, and select Options
from the last dialog box.

This icon denotes a note, which alerts you to important information.

This icon denotes a caution, which advises you of precautions to take to
avoid injury, data loss, or a system crash. When this icon is marked on the
product, refer to the Read Me First: Safety and Radio-Frequency
Interference document, shipped with the product, for precautions to take.

When symbol is marked on a product it denotes a warning advising you to
take precautions to avoid electrical shock.

When symbol is marked on a product it denotes a component that may be
hot. Touching this component may result in bodily injury.

bold Bold text denotes items that you must select or click in the software, such

as menu items and dialog box options. Bold text also denotes parameter
names.

italic Italic text denotes variables, emphasis, a cross reference, or an introduction

to a key concept. This font also denotes text that is a placeholder for a word
or value that you must supply.

monospace Text in this font denotes text or characters that you should enter from the

keyboard, sections of code, programming examples, and syntax examples.
This font is also used for the proper names of disk drives, paths, directories,
programs, subprograms, subroutines, device names, functions, operations,
variables, filenames, and extensions.

TBX-1316 High-Voltage Attenuator Terminal Block 2 ni.com

What You Need to Get Started

To install and use the TBX-1316, you need the following items:

❑ Hardware

– TBX-1316 terminal block

– One of the following modules:

• SCXI-1125 (recommended)

• SCXI-1126

• SCXI-1120/D

– One of the following chassis:

•SCXI

• PXI/SCXI combination

– One of the following:

• E/M Series DAQ PCI device

• E/M Series DAQ PXI module

– SH3232 shielded cable and cable adapter as required for your

application

❑ Documentation

– Read Me First: Safety and Radio-Frequency Interference

– DAQ Quick Start Guide

– SCXI Quick Start Guide

– TBX-1316 High-Voltage Attenuator Terminal Block Installation

Guide

– One of the following user manuals (application-dependent):

• SCXI-1125 User Manual

• SCXI-1126 User Manual

• SCXI-1120/D User Manual

– SCXI or PXI/SCXI combination chassis user manual

❑ Tools

– Number 1 and 2 Phillips screwdriver

– 1/8 and 3/8 in. flathead screwdriver

– Long nose pliers

© National Instruments Corporation 3 TBX-1316 High-Voltage Attenuator Terminal Block

– Wire cutter

– Wire insulation stripper

– Miscellaneous tools to permanently mount the enclosure

Installing the TBX-1316 Enclosure

Note Refer to the Read Me First: Safety and Radio-Frequency Interference document

before removing equipment covers or connecting or disconnecting any signal wires.

To install the TBX-1316 enclosure, complete the following steps:

1. Install an application appropriate UL-Listed external breaker
(disconnect) for each input line as follows:

a. Install the disconnect device(s) within close proximity of the

TBX-1316 and within easy reach of the operator.

b. Mark this enclosure as a disconnect device.

Note The TBX-1316 is intended for mounting in a permanent location. NI recommends

installing the enclosure in a permanent location whenever possible.

2. Securely mount the enclosure to the building per the local safety codes.
If the enclosure is mounted on plaster board (drywall), mount the
enclosure using four #14
four, 7.6 mm (0.3 in.) clearance mounting holes. Position the enclosure
so that all four screws are driven into wooden studs. Figure 1 shows the
clearance holes.

3. While referring to Figure 2, unlock and open the enclosure door using
a 3/8 in. flathead screwdriver.

4. While referring to Figure 3, complete the following steps to install the
protective earth (PE) ground wire.

Note The PE ground wire must comply with your local codes and be the same or larger

size AWG as the input signal wires.

a. Insert the PE ground wire through the PE ground strain-relief

collar.

b. Install a UL-Listed uninsulated closed-ring terminal, suitable to

your application, on the end of the PE ground wire.

c. Place the lock-washer over the ground-screw followed by the

PE ground terminal.

× 1 1/2 in. wood screws installed through the

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d. Place the provided lock washer over the end of the ground screw.

The screw should now have a ring terminal between two lock
washers.

304.80 mm
[12.000 in]

323.85 mm
[12.750 in]

e. Install the ground-screw/lock-washer into the enclosure, and

tighten it with a number 2 Phillips screwdriver.

f. Tighten the PE ground strain-relief collar.

342.90 mm
[13.500 in]

1000 V CAT I
600 V CAT II
50 µA MAX per channel

9.53 mm

[0.375 in]

25.4 mm

[1.000 in]

© National Instruments Corporation 5 TBX-1316 High-Voltage Attenuator Terminal Block

203.20 mm
[8.000 in]

254.00 mm

[10.000 in]

Figure 1. TBX-1316 Enclosure Mounting Hole Spacing