ENMET MED AIR 2000, Operation And Maintenance Manual, Page: 10 / 30

ENMET Corporation M
ED
A
IR
2000
6
3.2 Sample Air Supply
Tap the pipe or tank containing the breathing air and use appropriate fittings to connect the sample input hose. The
instrument is designed to operate from an air supply pressure of 50-55
PSIG
; adjust the regulator and set the pressure at
55
PSIG
. The flowmeter on the display panel indicates approximately 2 SCFH when the input pressure is 55
PSIG
.
The sample air exits the instrument from two separated ports on the back surface of the enclosure. Take care not to
obstruct these exit ports. After mounting the enclosure, they are not accessible.
Be sure that the red sample-calibrate valve handle on the right side of the enclosure is pointed down toward the sample
input port.
3.3 Power Supply
Plug the line cord in a source of 110 V
AC
power. The input power can vary from 100 to 240 V
AC
, 50/60 Hz; if other
than 110 V
AC
power is desired, the plug on the line cord must be changed.
Upon supplying air and power to the instrument:
ƒ
The green power on LED is lit.
ƒ The display backlight is lit, and numbers are given on the display.
The instrument may go into alarm briefly, but the sensors stabilize quickly. If the instrument persists in alarm,
acknowledge the alarm by pressing the
ALARM ACKN/AUDIO DEFEAT
switch. If alarm persists longer than 30
minutes, call ENMET customer service personnel.
3.4 Outputs
Two types of alarm outputs are available, relay contacts and optional 4-20mA outputs.
CO O2 DP N/A Fault LOOP
Figure 2A: Terminal Strip
3.4.1 Relay Contacts
Relay contacts are available for each alarm; these are SPDT , rated at 2.0Amp at 110 V
AC
, and may be latching or non-
latching as required by the application. They are accessed on the terminal strip at the bottom of the circuit board see
Figure 2 & 2A . The positions given in Table 1:
Table 1: Relay Contacts
Position Function Contact
1 CO Alarm NC
2 CO Alarm C
3 CO Alarm NO
4 O
2
Alarm* NC
5 O
2
Alarm* C
6 O
2
Alarm* NO
7 DP Alarm NC
8 DP Alarm C
9 DP Alarm NO
10 Not Used
11 Not Used
12 Not Used
* This relay is activated by both the deficiency and abundance alarms.
These relay coils are energized when they are in the non-alarm state; the contact conditions given above are for the
non-energized state, which is identical to the alarm state.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
NC C NO NC C NO NC C NO NC C NO NC C NO G
+
G
+
G
+
G