National Instruments FieldPoint FP-PWM-520 Operating Instructions Manual

OPERATING INSTRUCTIONS

FP-PWM-520

8-Channel, 5 or 24 V PWM
Output Module

These operating instructions describe the installation, features, and
characteristics of the FP-PWM-520. For details on configuring
and accessing the FP-PWM-520 over a network, refer to the user
manual for the particular FieldPoint network module you are using
with the FP-PWM-520.

Features

The FP-PWM-520 is a FieldPoint pulse-width modulated (PWM)
output module with the following features:

• Eight PWM output channels

• 0 to 100% duty-cycle capability with 12-bit resolution

• One millisecond period resolution

• Overcurrent protected outputs

• Sourcing outputs compatible with sinking inputs or 24 VDC
devices

• On/off LED indicators

• Hot plug and play operation

• 3,000 Vrms input-to-output isolation

• Double insulated for 250 V safe working voltage

• Independent configuration of the output period for each
channel from 1 to 65,535 ms in 1 ms increments

FieldPoint ™ is a trademark of National Instruments Corporation. Product and company names
mentioned herein are trademarks or trade names of their respective companies.

322139B-01 © Copyright 1998, 1999 National Instruments Corp. All rights reserved. June 1999

Installation

The FP-PWM-520 mounts on a FieldPoint terminal base
(FP-TB-xx) unit. Because of its hot plug and play operation, you
can install the FP-PWM-520 onto a powered terminal base without
disturbing the operation of other modules or terminal bases. The
FP-PWM-520 receives operating power from the terminal base.

To install your module, refer to Figure 1 and complete the
following steps:

1. Slide the terminal base key to either position X (used for any
module) or position 4 (used for the FP-PWM-520 module).

2. Align the FP-PWM-520 alignment slots with the guide rails on
the terminal base.

3. Press firmly to seat the FP-PWM-520 on the terminal base.
When the module is firmly seated, the terminal base latch locks
it into place.

Key

Latch

Alignment

Slot

Guide Rails

Terminal BaseI/O Module

Figure 1.

Install Your Module

Field Wiring

The terminal base provides connections for each of the eight output
channels and for an external supply to power f i eld devices.
Although the module does not need the external supply for its
internal operation, the output channels source current from this
external supply and require it to operate.

Each channel has one output terminal, V
terminals, COM (internally connected to the C terminal); and a
supply terminal, V

(internally connected to the V terminal).

sup

If you want to connect an external supply to power field devices,
connect to the V and C terminals of the terminal base, or to the V

FP-PWM-520 2 www.natinst.com

; two common

out

sup

and COM terminals for the individual channels. If the total current
supplied by the FP-PWM-520 channels is more than 4 A, route the
external supply to the V

and COM terminals. Otherwise, you can

sup

connect the external supply only to the V and C terminals. Figure 2
shows two examples of basic wiring connections.

–

CV

a. Total Current Less

Than 4 Amps

Figure 2.

–

V

out

COM

V

out

COM

CV

+

Load

Load

V

sup

V

out

COM
COM

V

sup

V

out

COM
COM

b. Total Current Greater

Than 4 Amps

Basic Field Connections (Two Channels Shown)

+

Load

Load

Table 1 lists the terminal assignments for the signals of each
channel. T erminal assignments and wiring diagrams are also listed
under the slide-in card on the front of the FP-PWM-520 module.

Table 1.

Terminal Assignments

Terminal Numbers

Channel

V

out

V

sup

COM

0 1 17 2, 18
1 3 19 4, 20
2 5 21 6, 22
3 7 23 8, 24
4 9 25 10, 26
5 11 27 12, 28
6 13 29 14, 30
7 15 31 16, 32

© National Instruments Corp. 3 FP-PWM-520