The circuit you require is possible, what is
the time frame within which you require it ?
You also need to tell the resolution you require
is it 130 or 130.0 and counter upto 9999 ? what
are the controls you want and the outputs
required if any.
You also need to tell the resolution you
require is it 130 or 130.0 and 130 1%
counter upto 9999 ? at least 0-999
what are the controls you want and the outputs
required if any.
a reset for counter and I would like the temp
sensor to have 4 sensors so I could surround a
pipe and any sensor would trigger circuit. The
unit would be mounted about 6-8 inches away
from sensors. Thinks a probe type sensor so it
can protrude from a plastic tube that will be
shaped to meet pipe or vent design.
i can design above with simple analog-digital
based circuits, microcontroller based designs
will take much more time but can be upgraded
No upgrade needed only the sensor mounting
locations will be needed at this point.
I might not need AC if the circuit can be
powered from 9 VDC battery like a Smoke
Hope this helps. This unit is more for
troubleshooting a air flow problem. If the
counter shows many 130 Degrees detected or alarm
is going off several times a higher priced
system for a forced air flow will be needed.
Currently no way to detect heat increases going
around vent so client doesn't want to purchase
forced air flow system. This is a safety device
so client can decide on this cheaper system to
monitor or a more expensive permanent fix. I
will need a PCB setup after I can test the
circuit in test environment.
The temperature in a pipe is monitored with
four RTD Pt-100 Sensors, The type of probe could
be Extruder RTD probes with Bayonet or
Compression Fitting, Get it from Omega. The
temperature at four points are measured by
Temperature Module and compared with one
setpoint 0-200 deg C, an alarm output LED out-a
goes ON when the measured temperature exceeds
the common setpoint.
to Design Service and Projects
a. do you need individual setpoints for all the
four points you measure ?
b. is the temperature deg C or deg F,
centigrade or Fahrenheit ?
c. do you need a relay output when the LED goes
ON to turn off the heater ?
d. the time taken to measure 4 points will be 4
seconds is that fast enough ?
e. do you need a display of the measured
temperature as shown above ?
The Analog Timer Module can be set from 0- 30
minutes. If out-a remains high even after set
time a out-b alarm goes on with a relay output,
the relay contacts can be used to turn off a
heater or sound a buzzer.
a. do you want to use a digital timer instead ?
I'm open. Trying to keep costs down
b. do you need a solid state relay output ?
Used like a smoke detector. Alarm to notify
client to check air flow. This is in case the
air flow stops.
Whenever out-a goes high and low the Counter
Module counts from 0000 to 9999. The counter can
be reset at any time by pressing a button. This
will count the number of times temperature in
pipe went above the setpoint.
a. do you need a preset like "150 times" for the
counter to sound an alarm ?
NO The alarm should sound if temp is 130 or
above and stays that way for 3 minutes.