TSI Instruments 4000 Series User Manual

29
1. Store a fixed pressure value in the instrument. If the typical actual
pressure is known and relatively constant, you can store the
estimated pressure in the instrument’s memory. You can enter this
fixed pressure via any of the serial protocols. Examples of this
method include a relatively constant backpressure caused by
downstream hardware or a correction for high altitude operation.
The default pressure is 101.3 kPa. This pressure cannot be saved
in the nonvolatile memory—your system must refresh this data
each time the flowmeter is powered up or reset. See command
SPnnn.nn in Appendix C for more information. See the Command
Set sections.
2. Supply a real-time pressure signal to the flowmeter. If you need the
best possible accuracy or if the pressure fluctuates greatly during
normal operation, you should supply the flowmeter with a signal
from a calibrated, user-supplied pressure sensor. This pressure
information can be supplied to the instrument via any of the serial
interfaces. The meter also accepts an analog pressure input
signal. See the Command Set
section.
See the graphs on the following page for the effects of pressure at
various flow rates.

TSI Instruments 4000 Series Specifications

General

Measurement Parameters	Velocity, Temperature
Data Storage	10, 000 data points
Accuracy	±0.015 m/s or ±1% of reading
Particle Size Range	Not applicable
Display	LCD
Operating Humidity	0 to 95% RH (non-condensing)

Summary

Chapter 1 - Models and Accessories

Model Designations

Details specific model numbers, gas calibration, flow range, and adapter types.

Chapter 2 - Measurements Available

Flow Rate Measurement

Explains how flow rate data is obtained via analog or serial interfaces.

Chapter 4 - Design Considerations, Mechanical

Important Safety Notes

Covers hydrogen safety and intrinsic safety aspects of the flowmeters.

Filtration Requirements

Chapter 5 - Design Considerations, Electrical

Power Requirements

Specifies voltage, current, and connection type for the flowmeter's power supply.

Output Signal, Analog

Describes the default analog output voltage range for mass flow measurement.

Chapter 7 - Specifications

Flow Measurement

Details measurement ranges and accuracy for different models and gases.

Accuracy (continued)

Provides accuracy specifications for Nitrogen and Nitrous Oxide gases.

Appendix C - Digital Serial Interface

Command Set Summary

Overview of data format, buffering, and command structure for serial communication.

Commands for Flow Rate, Volume, and Temperature Measurement

Details commands for acquiring flow rate, volume, and temperature measurement data.

Measurement Setup Commands

Setup Commands for Analog Output