Dwyer Instruments 670 Series User manual

Series 670 Hood Monitor
Specications - Installation and Operating Instructions
Bulletin AV-670
®
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

Operator Display Panel
Built-in AIRFLOW
SENSOR
LED indicators
Function buttons
Calibration.
ENTER- also used
as Mute button for
audible alarm
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

MOUNTING BRACKET
1.67
[42.55]
1.67
[42.55]
4.65
[118]
4.96
[126]
0.16 [4]
0.16 [4]
3.35
[85]
PANEL CUTOUT DIMENSIONS
4.65˝ x 3.35˝ [118 mm x 85 mm]
2 x FIXING HOLES
2.5 mm DIAMETER
FOR 2 x No. 4
SELF TAPPING
SCREWS PROVIDED
3-29/64
[87.88]
5-45/64
[145.03] 4-9/16
[116.08]
13/64
[5.08]
1-1/16
[27.10]
4-61/64
[125.98]
3-17/64
[83.06]
2-1/64
[51.05]
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

SPECIFICATIONS
Service: Fume hood face velocity air ow.
Alarm Range: 30-400 FPM (0.15-2.0 m/s).
Alarm Indication: Red LED & audible alarm.
Low Air Velocity Alarm Delay: Fixed 5 s.
Display: Visual LEDs: Red: Alarm, Green: Normal.
Horn Silence: Yes-temporary and permanent.
Accuracy: Face velocity ±10%.
Operating Temperature: 55-86°F (13-30°C).
Storage Temperature: -40 to 150°F (-40 to 65°C).
Power Requirement Input: 15 VDC 500 mA; 120 VAC, 60 Hz power transformer included.
Relay Output Low Air Flow Alarm: 5 amps @ 250 VAC.
Relay Input For Night Setback: 2 wire rated for 24 VDC usage.
Sash High indication: Using a two wire micro switch or 3 wire proximity switch input, rated for 24 VDC usage.
Comm Port: RS232- Can be connected via serial interface to LAN network.
Mounting: Semi ush, ush or surface mounted when using included bracket.
Agency Approval: CE.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

100mm
100mm
No rm al Sash
work in g he ig ht.
eg . 500m m
670
670 Face
Open to the
laboratory
25mm
Female adapter
Fume cupboard
outer skin
Fume cupboard
inner skin
25mm
Male
bush
25mm Tube
4.0 Fume Hood Installation
It is very important to position the Series 670 airow sensor in the correct position to give long term stable reading of
the face velocity. Please read the INSTALLATION NOTES below and if in doubt contact us for further advice.
Installation Notes:
1. The Series 670 must be positioned where it can “see” the room pressure of the laboratory. The back connection
spigot of the sensor is designed to accept a 25mm OD tube which should be connected to the inner chamber of
the fume hood. (This tube and ttings is known as the “vent kit”). The ideal position for the end of the 25mm tube
for most fume hoods is 100mm back from the sash glass and 100mm higher than the normal sash opening height
through the inner side wall.
2. If possible mount the sensor on the front of the fume hood and use a short length of tube. Tube lengths of more
than 1 meter or smaller diameter will restrict the airow through the sensor. This will lead to too much sensitivity
being required to calibrate the unit which can lead to some instability of the reading or incorrect readings at low
velocities.
3. For fume hoods with a single skin side wall or a double skin with a small gap between them it may not be possible
to achieve the ideal sensing position using a exible tube. With a single skin side wall it is possible to x the sensor
on the outside of the fume hood and connect directly to the inner chamber in the ideal position. This method can
only be used for up to two fume hoods when they are positioned side by side (using the two outer walls). An
alternative method is to mount the sensor on the front of the fume hood and connect using a short exible tube to
a rigid wall tube attached to the inner side wall. The open end of this rigid wall tube should be positioned in the
‘ideal position’, i.e., 100mm back from the sash and 100mm higher than the normal sash opening. Fume hoods
with a high internal height can present a difculty because the tube length to reach the ideal position may be longer
than 1 meter. In this case it is better to use a tube no longer than 1 meter which may result in a sensing position
higher than the ideal. When tting a sensor to a ’narrow wall’ fume hood for the rst time it may be necessary to try
various combinations of rigid and exible tube to nd the best combination and position.
4. The sensor should not be mounted in a position were it is subject to drafts from the laboratory air input or ventilation
system.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

4.0 Fume Hood Installation
Installation using Duct Connection
When using the Duct Connection method the 1/4˝ connection tube acts as a ow restrictor (due to the higher
pressure in the duct). Use a 6 ft tube for pressures below 0.4 in w.c. and a 12 ft tube for higher pressures
670
MOUNTED ON
FRONT
OF FC
STANDARD
25mm SENSOR TUBE
ADAPTER THROUG
H
INNER SIDE WALL
670
MOUNTED ON
FRONT
OF FH
1/4 INCH SPIGOTS
CLEAR PVC
1/4 INCH SENSOR TUBE
SPIGOT CONNECTOR
FITTED INTO
EXTRACT
DUCT
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

Wiring Diagram
Note: The Sash High alarm can operate with the Micro Switch OR the Proximity Switch. Both connection points are
available as standard.
Flying lead with plug
connection for PCB
and SM6 airflow
sensor 12V DC
Remote
SM6 Airflow Sensor
(Optional)
Sash High
Micro-switch
(Optional)
Flying lead from Proxy
switch with plug
connection for PCB
12V DC
Sash High
Proximity switch
(Optional)
PSU
Flying lead with plug
connection for PCB
15 V DC
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

External Electrical Connections
The alarm unit will have the following connection points:
Input 1 - Volt free relay input - (close contact to activate the input).
This input is congured as:
NIGHT SETBACK
Output R1 - Volt free relay output - (contact closes on activation).
This input is congured as:
LOW AIR ALARM
Sash High Input - a. Connection point for Sash High micro switch. (Switch contact to close and remain closed in
Sash High condition).
b. Connection point for Sash High proximity switch. (Switch contact to close and remain closed
in Sash High condition).
Note: Use input a. OR input b. for the Sash High alarm.
Remote Airow Sensor - Plug in connection for airow sensor.
Note: The remote Airow Sensor socket will only be available for units ordered without the built-in
Airow Sensor.
Com Port - To enable connection to Laptop or PC.
Power supply - Low voltage DC power supply 15V DC.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

1.1 General Description
All systems comprise of the following components:
1 - 670 Alarm unit 1 - IOM
1 - AC power supply 1 - Vent kit
1 - 24˝ tubing 1 - Mounting bracket w/screws
Operator Features - the alarm has the following operator features:
Safe LED - Green LED (Not ashing) will be displayed if the airow is greater than the Low air alarm point.
Alarm LED - Red LED (Not ashing) will be displayed if the airow is lower than the Low air alarm point.
Sash High - Red LED (Flashing) will be displayed when the Sash is raised above the max safe working opening.
Audible Alarm - The Audible alarm will sound ( can be muted ) in the Air Fail and the Sash High alarm condition.
Night Set-back - When the Night Setback input is activated the Audible alarm will be muted and the Green LED will
ash on/off.
ENTER - The alarm has an Enter button - this is multi-functional as follows:
Pressing Enter momentarily when Low Air alarm is sounding will mute the alarm.
Pressing Enter momentarily when Sash High alarm is sounding will mute the alarm and initiate a repeat
timer that will re-sound the alarm if the Sash is not lowered to a safe position before the end of the time
period.
Pressing Enter for 5 s will gain access to Calibration mode.
SET - Press SET for 10 s to permanently disable the audible alarm. The audible alarm will beep 3 times to
indicate a successful permanent audible disable. If audible alarm is permanently disabled, press SET for
10 s to enable. The 3 beep audible signal will notify a successful audible enable has been
programmed. Also used during the airow Calibration of the alarm.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

1.2 Alarm Conguration/Calibration
The alarm is supplied with a factory conguration.
The only part of the conguration that can be changed is the setting for the Sash High timer delay and the percentage
gure for the Low Air alarm point when using the two point calibration mode.
The alarm has two modes for the calibration of the airow alarm point. These two modes are selectable via a
‘jumper connection’ on the back of the alarm PCB. The jumper is labeled as CAL and is situated on the edge of the
PCB above the Com port.
The two calibration modes are:
a. Single Point Calibration (with the Jumper connected) - The airow is reduced mechanically (using balance
damper or slowing down the extract fan) to the Low Air alarm point and this air ow is ‘captured’ by the alarm.
The airow is then restored to the normal operating value and the Low Air alarm will activate if the airow
subsequently falls to the alarm point.
b. Two Point Calibration (with the Jumper not connected) - This is a two point calibration method. The airow
is set to the normal operating value and this value is ‘captured’ by the alarm and taken to be 100%. The airow
is then increased to one and a half times the normal operating value and this value is ‘captured’ by the alarm and
taken to be 150%. The Low Air alarm will then activate if the airow subsequently falls to 80% of the normal
operating value.
Note: For fume hoods where it is not possible to use the side wall sensor connection the sensor can be connected
directly to the extract duct using adapters and a 1/4˝ PVC tube - see installation section for details. Only the Single
Point Calibration method can be used for this conguration.
See ‘Quick Start Installation’ below for details of the Calibration procedures.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]