Siemens QFM2100 User Manual

Installation Instructions
Document No. 129-413
October 13, 2004
Q-Series Relative Humidity (RH) and
Relative Humidity & Temperature (RH/T) Duct Sensors
Product Description
Relative Humidity (RH) and Relative Humidity &
Temperature (RH/T) duct sensors monitor the
relative humidity or the relative humidity and
temperature in a duct, depending on the model.
Sensors are directly wired to the controller via
twisted pair and/or three conductor cables
(18 to 22 AWG). The number and type of cables
required depends on the model selected. All field
wiring is terminated in a terminal block on the sensor
body.
Product Numbers
Table 1. Relative Humidity Only.
Product
Number
Humidity
Signal
Accuracy
♦
QFM2100 ±5%
QFM3100
0 to 10 Vdc
±2%
QFM2101 ±5%
QFM3101 ±2%
QFM4101
4 to 20 mA
±2% Certified
Table 2. Relative Humidity and Temperature.
Product
Number
Temperature
Signal
Humidity
Signal
Accuracy
♦
QFM2160 ±5%
QFM3160 ±2%
QFM4160
0 to 10 Vdc 0 to 10 Vdc
±2% Cert.
QFM2171 ±5%
QFM3171 ±2%
QFM4171
4 to 20 mA 4 to 20 mA
±2% Cert.
QFM2110
Pt 1KΩ
QFM2120
Ni 1KΩ
QFM2140 T1 PTC
±5%
QFM3110
Pt 1KΩ
0 to 10 Vdc
±2%
♦
Applies to humidity only
NOTE: Sensor tips on QFM31… and QFM41…
models are field replaceable.
Additional Reference Documents
Product Number Technical Instructions
QFM21… 155-748
QFM3160 155-749
QFM4160 155-750
Required Tools
• Phillips screwdrivers, #1 and #2
• Wire cutters/strippers
• Medium flat-blade screwdriver
• Tape measure
• Medium-duty electric drill
• Marker or pencil
• No. 26 (0.147-inch) drill bit
• Small level
• 7/8-inch drill bit or hole saw
• Two No. 8 × 1-inch sheet metal screws
Expected Installation Time
One hour
Prerequisites
• Ensure that the appropriate field wiring is
installed.
Appropriate wiring is one or more twisted
pairs, or three conductor cables (plenum or
non-plenum as required), within the
maximum wiring run length for the individual
equipment controller. The maximum
recommended length is 750 feet (229 m).
• Ensure that all wiring complies with National
Electric Code (NEC) and local regulations.
Mounting Information
Locate the sensor:
• In the center of a duct.
• Away from fans, corners, heating and cooling
coils, and so on.
• Where it receives adequate airflow for proper
operation.
Item Number 129-413, Rev. 011 Page 1 of 3

Siemens QFM2100 Specifications

General

Brand	Siemens
Model	QFM2100
Category	Accessories
Language	English

Summary

Q-Series RH/T Duct Sensors Overview

Product Description

Details the function and wiring of RH and RH/T duct sensors for monitoring duct conditions.

Product Numbers and Specifications

Lists available sensor models, signal types (0-10 Vdc, 4-20 mA), and accuracy ratings.

Required Tools for Installation

Lists all tools and hardware needed for installing the duct sensors.

Installation Prerequisites

Ensures proper field wiring and compliance with electrical codes before installation.

Mounting Location Guidelines

Provides recommendations for optimal sensor placement within a duct for accurate readings.

Installation Instructions

Sensor Mounting Bracket Installation

Details steps for attaching the sensor mounting bracket to the duct using screws.

Direct Sensor Installation

Explains how to mount the sensor directly to the duct without a separate bracket.

Wiring Connections

Covers attaching conduit/plenum wire and connecting field wiring to the sensor base.

Wiring Diagrams

RH Sensors 0-10 Vdc Wiring

Diagram for connecting RH sensors with a 0 to 10 Vdc signal output.

RH Sensors 4-20 mA Wiring

Diagram for connecting RH sensors with a 4 to 20 mA signal output.

RH/T Sensors 0-10 Vdc Wiring

Diagram for RH/T sensors outputting 0 to 10 Vdc for both temperature and humidity.

RH/T Sensors 4-20 mA Wiring

Diagram for RH/T sensors outputting 4 to 20 mA for both temperature and humidity.

RH/T Thermistor RTD 0-10 Vdc Wiring

Diagram for RH/T sensors using Thermistor RTD with a 0 to 10 Vdc output.