Seikom Electronic RLSW4 Airflow Monitoring Device User Manual
- June 13, 2024
- SEIKOM ELECTRONIC
Table of Contents
Airflow monitoring device
Manual for air flow monitor
RLSW4 / RLSW4R
RLSW4 Airflow Monitoring Device
Our products correspond to the
requirements of the European guidelines
WEEE 2012/19/EU – RoHS 2011/65/EU
The RLSW4 is a calorimetrical air flow monitor the is a cheap access to the
world of watching air flows and is an alternative to known pressure cell, vane
switches and fan belt monitors.
You can install the device with its flange or its PG7 simply and fast. With
its built in potentiometer the switch point may be set infinitely variable.
The transistor output is connected at flow and the yellow LED enlightens.
Differences in the media temperature are compensated automatically.
Proper usage
The RLSW4 is to be used as an air flow monitoring device watching gaseous media within its technical data. Its application area is e.g. ventilation and air conditioning installations, filter watching, supply and exhaust gases.
Measuring principal
A temperature-sensitive resistor is heated according to the calorimetric measuring principle. The temperaturesensitive resistor is heated by a second resistor. A flow in the medium dissipates heat from the measuring resistor, causing the resistor temperature an impedance to change. This temperature change is evaluated. Since both the velocity and the temperature of the flowing medium affect the dissipated heat, a relationship must be created between flow and temperature. For this purpose, a second temperature-dependent measuring resistor is located next to the first one. The second measuring resistor (temperature compensation) is not heated and is only used for the temperature measurement.
| flow >= switch point | signal output switches | yellow LED enlightens |
|---|---|---|
| flow < switch point | signal output does not switch | yellow LED does not |
enlighten
Technical data
| Type | RLSW4 | RLSW4R | RLSW4R/140 |
|---|---|---|---|
| Article No. | 74825 | 74825/R | 74825R/140 |
| supply voltage | 24V AC/DC | 24V AC.DC | 24V AC/DC |
| supply voltage tolerance | +/-5% | +1-5% | +/-5% |
| signal. supply voltage | – | – | |
| power consumption | WA | 1VA | WA |
| ambient temperature | -20..4- 0-C | -20..+60-C | -20..+60- C |
| signal output. flow | 1 NOC | 1 NOC |
Relay output current- and contactload
Minimum switching load| | 250VAC. 5A. 1.2kVA (with optional
plug: 150VAC. 5A. 0.75kVA)
10mA / 5V DC| 250VAC. 5A. 1.2kVA (with optional
plug: 150VAC. 5A. 0.75kVA)
10mA / 5V DC
switch function at flow| –| relays connects| relays connects
signal at flow| yellow LED| yellow LED| yellow LED
transistor output| PNP. max 150mA| relays| relays
| | |
media temperature range| -10..+80t| -10..+80-C| -10..+80-C
temperature gradient| 15K/min (optional: 30K;rnin)| 15K/min (optional:
30K/min)| 15K/min (optional: 30K/min)
switch point| set up with potentiometer| set up with potentiometer| set up
with potentiometer
metering range| 0.1 – 15m/s| 0.1 – 15mIs| 0.1 – 15m/s
| | |
sensor| installed| installed| installed
immersion depth approx.| 50mm (optional: 140mm)| 50mm| 140mm
process connection| PG7. flange| PG7. flange| PG7. flange
sensor material| MS58. nickel plated
(optional stainless steel)| MS58. nickel plated
(optional stainless steel)| MS58. nickel plated
(optional stainless steel)
pressure resistance| 10bar| 10bar| 10bar
| | |
electrical connection| 4 clems. 2.5mm= (optional M8
plug ceonnector)| 4 clems. 2.5mm= (optional M8 plug
ceonnector)| 4 clems. 2.5mm= (optional M8 plug
ceonnector)
protection class housing| IP65| IP65| IP65
protection class sensor| IP67| IP67| IP67
imensions| L=30mm: W=50mm: H=65rnm| L=30mm: W=50mm: H=65mm| L=30mm: W=50mm.
H=65min
| | |
mark of conformity| CE| CE| CE
accessory| flange 14,2mm| flange 14.2mm| flange 10/14,2mm
Attention!!
Connection and commissioning must be performed by properly authorized and
qualified personnel!
Connection to mains supply (L, N) must be made by means of a protected
isolating switch with the usual fuses. As a matter of principle, the General
VDE Regulations must be complied with (VDE 0100, VDE 0113, VDE 0160).
Installation Instruction:
- The sensor should be mounted in such a way that the air flow passes through the lateral opening. The marking is intended as an assembly aid.
- Installation where there is low turbulence, if possible.
- Do not install directly behind bends (distance approx 10x bend radius).
- Install the probe in the middle of the duct where possible (distance at least 1/3 of the duct diameter from the wall).
- Do not install directly behind the heating register (rapid changes in temperature may lead to the measured values being falsified.
Cleaning:
The airflow sensor contains a sensor element which is sensitivity to
mechanical loading and which must not be touched with hard and pointed
objects. Any cleaning that may be necessary is possible in water (also with
addition of detergents). Let the unit drip off and dry renewed start-up.
Electrical connection
Optional plug connector
| Pin | Colour | connection |
|---|---|---|
| 1 | brown | +Uv |
| 2 | white | GND |
| 3 | black | contact 13, NOC |
| 4 | blue | contact 14, GND |
Dimension:
RLSW4R/140 immersion sensor tube differently about 130mm.
Setting the switch point
The relationship between air velocity and impedance change is non linear. In
the lower flow velocity range, the impedance change is very large. In the
upper flow velocity range, however, identical changes in flow velocity result
in increasingly smaller impedance changes. When the switch point is set, it is
important to note what change is to be monitored because different settings
have certain disadvantages.
Note the following requirements:
Small flow change in high flow velocity range: The switch point must be
selected very close to the normal flow reading since flow changes only lead to
a very small change in the measured value. Since temperature compensation
takes place with certain delay after the actual temperature change has
occurred, this switch point setting is only suitable for the applications
which have slow temperature changes in the medium.
Small flow change in low flow velocity range: The switch point can be selected
at a greater interval from the normal flow reading because a change in flow
velocity causes a very large change in the measured value. A temperature
change has not effect on switching behaviour.
Large change in flow rate:
A Yes/NO statement is usually required here (e.g. fan running or fan
stationary). You can therefore select a safety clearance which is so large
that neither temperature changes nor turbulences can have an affect on
switching behaviour.
Commissioning RLSW4 (R)
Commissioning the RLSW4 you need to follow these points:
- install the device
- connect the device regarding to the manual
- set potentiometer “sensivity” (the unpainted trimmer to the right of the screw) to minimum sensivity
- switch on supply voltage; The device is instantly operational.
- switch on the working flow
- turn potentiometer “sensivity” slowly to maximum until the yellow LED enlightens and the transistor output changes. To ensure proper operation you may turn the potentiometer slightly over the switch point.
- to check for proper operation, please lower or switch off the flow. The yellow LED should darken and the transistor output disconnects.
The monitoring device is now set to watch the flow.
Frequently asked questions
| Problem | Cause | Sollution |
|---|---|---|
| RLSW4 does not operate | wrong or none supply voltage | check the supply voltage |
| RLSW4 does not react on flow | sensor is installed wrongly | check the sensor’s |
installation
RLSW4 shows unusual response| sensor is highly polluted| clean the sensor,
refer to the regarding page in this manual
Mistakes and misprints are not to be excluded. All information „without
guarantee“.
03/2022
SEIKOM-Electronic GmbH & Co. KG
Fortunastr.20D-42489 Wülfrath
Telefon: +49(0) 20 58/20 44
Fax: +49(0) 20 58 / 79 111
E-Mail:[email protected]
Internet:http://www.seikom-electronic.de