Honeywell Midas User Manual

Midas
®
Gas Detector
4-20
4-20 mA
Controlled
Current Source
Internal
Power
Loads
J4
INT EXT
J5
EXT INT
11
10
9
MIDAS
Simplified Internal Schematic
2
1
-
+
Cabinet
Shielded Cable
RJ-45
8
7
2
3
4
5
6
1
DC
PWR
+24 V
COM
NO
NC
Relay3
Relay2
Relay1
ON
SW
OFF
11
10
9
Analog Current
Loop 4-20 mA
INT EXT
EXT INT
-supply
J5
J4
+supply
J1
NO
NC
J2
NO
NC
J3
PYROLYZER
CONNECTOR
Relay1
}
Relay2
}
Relay3
}
+
24
VDC
-
HI
EXC
+
24
VDC
-
Sense
Resistor
Loop
Supply
Not optically isolated
HA71
Analog Input Card
R2
R1
ANALOG INPUTS
R3
R4
R7
R6
R5
+EXC-
DC PWR
TB2
R8
JP1
ST-71 ANALOG INPUT BOARD
0010-1115 ASSY# 10-0158
J2
J1
CH1/9
EXC HI
CH7/15
HIEXC
CH3/11
EXC LOHILO
CH5/13
LOHI EXC LO
CH2/10
HIEXC
CH8/16CH4/12
EXC LOHI CXEOL
CH6/14
EXC LO OLIH HI
EXC LOHI
4 Wire 4-20mA
Transmitter
+Pwr
Sig
+
-
24 VDC
Power Supply
Diagram 4-19. Midas
®
to HA71 4-Wire Connection

Honeywell Midas Specifications

General

Power Supply	24 VDC
Detection Technology	Electrochemical, Infrared
Sampling Method	Diffusion
Display	LCD
Communication	Modbus RTU, 4-20mA
Operating Temperature	-20°C to +50°C
Humidity Range	0% to 95% RH (non-condensing)
Target Gas	Multiple gases
Response Time	< 30 seconds
Operating Humidity	0% to 95% RH (non-condensing)
Outputs	4-20mA
Protection Rating	IP66
Certifications	ATEX, UL, CSA
Detection Gases	Oxygen (O2), Carbon Monoxide (CO), Hydrogen Sulfide (H2S), Methane (CH4), and others