Michell Instruments XTC601, Руководство пользователя

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XTC601 User’s Manual
Michell Instruments 41
APPENDIX A
• A high alarm switches on when % O
2
is above the set point and switches
off when % O
2
is below the set point – Hysteresis
• When the instrument is warming up (cell temperature not stabilized) both
relays are OFF
4.5.7 Analog (4–20mA) Inputs and Sensor Excitation Voltage
PIN 6 PIN 5 PIN 4 PIN 3 PIN 2 PIN 1
Ch2
I/P
-
CH2
I/P
+
Ch2
Exc.V
Ch1
I/P
-
Ch1
I/P
+
Ch1
Exc.V
The XTC601 features 2 input channels for 4–20mA signal from external instruments such
as pressure transmitters or other devices to compensate for pressure or background gas
influence.
The input configured as
EXT SENS EXT SENS
(External Sensor) can be viewed on the Secondary
Parameters Page under the heading
EXT I/P EXT I/P
(External Input).
NOTE 1: Standard Analyzer:
Channel 1 = External compensation input
Channel 2 = External sensor input
HCG Analyzer:
Channel 1 = External phase input
Channel 2 = External sensor input
NOTE 2: Excitation voltage = Same as power supply ±1 V if JMP4 connected
across top 2 pins and 15 ±0.5 V (max 100mA per channel) if JMP4 connected
across bottom 2 pins.
NOTE 3: HCG version only:
To select phases externally, current signals within the following
rangesshould be applied to channel 1:
1. Phase 1 = 7mA to 9mA
2. Phase 2 = 11mA to 13mA
3. Phase 3 = 15mA to 17mA
4.5.8 Light Guide
The optional light guide can be fitted to the left hand cable entry. If this is required for
the Hazardous Area version of the analyzer this must be specified at time of purchase
order. Only one light guide can be fitted to each analyzer.
(PL4 – Green)