Honeywell Midas User Manual

Midas
®
Gas Detector
4-15
4-20 mA
Controlled
Current Source
Internal
Power
Loads
J4
INT EXT
J5
EXT INT
11
10
9
MIDAS
Simplified Internal Schematic
2
1
-
+
Sieger System 57
Quad Relay Interface Card
05704-A-0121
with
4 Channel Control Card
05704-A-0145
Cabinet
(01) 17
(S) 15
36
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
-
+
24
VDC
-
Note:
The above schematic shows the MIDAS connected
to channel 1 on the 5704 card. The terminal numbers
for all four channels are as follows:
MIDAS Function Loop + Loop -
Midas Terminal Number
Color in this figure
5704 Channel 1 Terminal
5704 Channel 4 Terminal
5704 Channel 3 Terminal
5704 Channel 2 Terminal
11
Brown
15
22
21
16
System 57 Function S
10
Blue
17
24
23
18
01
17
15
System 57
Relay/Field
Interface Card
5704 Control Card
+
24
VDC
-
Sense
Resistor
Loop
Supply
Not optically isolated
Diagram 4-14. Midas
®
to 5704 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