MGS Installation and Operation Manual
1000-0085 Rev 0
21
Section 5. Configurations
5.1. Overview
Function
Description
Time Delay
Available on the audible alarm and relay to avoid false
alarms. This is set with jumpers.
The default delay is 0
minutes.
You may wish to set to 15 minutes during start up.
See Figure 2 and Figure 3 for setting the jumpers.
Audible
Alarm
The units have an internal audible alarm. You can disable
this by jumper, but the
default setting is “enabled”
in
compliance with EN378. See Figure 2 and Figure 3 for
setting the jumpers.
Output
Decide which output is required: 4-20mA, 1-5V, 0-10V, relay
outputs, etc. See Figure 2 and Figure 3 for setting the
jumpers.
5.2. Adjusting the Alarm Set Point
This process is the same for all versions using pot P1 and test points 0V and
REF1.
Step
Adjusting the Alarm Relay
1
Locate Pot P1 and use it to adjust the set point at which the relay
activates.
2
Monitor the output between test points 0V (negative) and REF1
(positive) until the correct setting is reached. See example below.
Example:
For a sensor range of 0-1000 ppm, calculate the voltage to set the
relay at 100 ppm.
𝐀𝐥𝐚𝐫𝐦
𝐏𝐨𝐢𝐧𝐭
𝐕𝐨𝐥𝐭𝐚𝐠𝐞
=
𝐀𝐥𝐚𝐫𝐦
𝐕𝐚𝐥𝐮𝐞
×
𝟓
𝐕
𝐌𝐚𝐱
𝐑𝐚𝐧𝐠𝐞
𝐀𝐥𝐚𝐫𝐦
𝐏𝐨𝐢𝐧𝐭
𝐕𝐨𝐥𝐭𝐚𝐠𝐞
=
𝟏𝟎𝟎
𝐩𝐩𝐦
×
𝟓
𝐕
𝟏𝟎𝟎𝟎
𝐩𝐩𝐦
=
𝟎
.
𝟓
𝐕
So the alarm voltage setting is 0.5 Volts.