Swakath

Swakath/Comments.txt

@@ -0,0 +1,39 @@
+Name: Swakath
+
+1.	Question text:
+Design a system using this Honeywell ammonia sensor (https://drive.google.com/file/d/164WvPD7GauvseOfH-K3v8iZ4YYmQFkq-/view?usp=sharing ) to detect when ammonia concentration in ambient atmosphere exceeds 100 ppm an alert an operator in a control room about 100m away. This device will be mounted in various sections of an industrial processing plant. The complete plant will need a fairly large number (~20) of sensors so unit costs needs to be kept under control. Also, once mounted it will be very difficult to remove/service/repair the sensing devices.
+
+
+2.	Design summary:
+	Overall approach is fine.
+	Good work finding th module that has a 4-20mA output directly
+
+
+3.	Block diagram
+	Why is there a common supply for both the sensor module and the receiver module?
+	They might be physically very far apart!
+	
+4.	Power supply design
+	The brick module may end up being underpowered for what you need.
+	Also, why design a rectifier filter and then use the module?
+	Power in a current-driven system is indeed tricky - you need to factor in the worst case 
+	voltage drop and times the current is power. 
+
+5.	Industrial Design:
+
+
+6.	KICAD Design
+	Schematic:
+	All good - good use of decoupling caps.
+	No Power on LED?
+	How exactly is the fault opamp working?
+	Also the OpAmp outputs are +/-12V. If you're connecting this to the uC you need to scale down to 5V or 3v3.
+
+	
+	PCB:
+	No Mounting holes?
+	Good use of pours
+	
+7.	Pricing / BOM / Assembly
+	The question asked for 2 prototypes - meaning two systems with about 20 sensor modules each.
+	But I guess this interpretation is fine too.