Dynisco ATC770, Инструкция по установке и эксплуатации

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2.5 P
RESSURE
& R
EMOTE
S
ET
P
OINT
I
NPUTS
C
OMMON
S
PECIFICATION
Common Mode Rejection Ratio: 120 dB @50/60 Hz
Normal Mode Rejection Ratio: 60 dB @ 50/60 Hz
Reference Accuracy:
±
0.2% of full scale value
±
1 digit @ 25
±
10
°
C and nominal power voltage.
Operative accuracy - temperature drift:
<300 ppm/
°
C of full span for current, voltage and strain gage input
2.6 D
IGITAL
I
NPUT
S
PECIFICATION
Digital Input: One input from contact closure (voltage free). It may be keyboard programmable for
the following functions:
• alarm reset
• peak reset
• alarm and peak reset
NOTE: This input is not isolated from main input. A double or reinforced insulation between
instrument output and power supply must be guaranteed by the external device.
Opto-isolated Digital Input: Four optional digital inputs are provided for control purposes. The
interface circuit is opto-isolated with respect to the CPU and analog inputs.
DIG1: This contact acts as an automatic / manual switch, if it is enabled by the proper parameter
(closed means manual mode, open means automatic mode).
DIG2: Control output value increase.
DIG3: Control output value decrease.
These three contacts are used to increase / decrease the output value with a linear, not exponential,
rate of change (about 20 seconds for a full scale variation from 0 to 100%).
NOTE: Use for manual mode only. Not used for set point adjust.
DIG4: This contact is used to switch the controller from automatic to manual mode setting to zero
the control output. When this logic input is closed the transfer from manual to automatic mode by
the front panel is inhibited while the user may modify the control output. To return to automatic
mode the logic input should be de-activated.
2.7 A
LARMS
S
PECIFICATION