Minebea Intec MP30, Руководство пользователя

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This application uses the MP30 indicator to monitor the weight of a liquid
storage tank. The indicator is connected directly to 4 - 350 ohm load cells,
using the internal 10 VDC excitation source. The average sensitivity of the load
cells are 2.1 mV/V. This yields a full scale output of approximately 21 mV
which is within the maximum input of 24 mV of the indicator’s low range.
Calibration of the indicator can consist of any two
arbritrary scale points. In this application, the low scaling
point was determined by metering in 1,000 liters of liquid
into the tank and the high scaling point, 10,000 liters. For
this application, the indicator scaling values are:
The indicator registers the output of the load cells at
these points and corresponds them to the readout display
values.
A four output relay setpoint card is installed.
Two of the relays provide HI and LO level alarm
outputs. These alarms are programmed to trigger on the
Gross liquid weight of the tank.
The remaining alarm outputs are used for a simple loss-of-
weight filling application. One is programmed as a low-acting
alarm, triggering on the Net liquid weight. Each filling
operation is started with a Tare Out / Tare In sequence. This
opens the filling valve and when the target setpoint is
reached, the valve is shut off. The valve remains off until
a tare operation is repeated, thereby restarting the filling
operation. The fourth output is connected in series with the
fill output to disable filling during the interval of the Tare Out
and Tare In operation.
A Linear DC Output plug-in option card is also installed. This
card provides either 10 V or 20 mA conditioned and scaled output for
remote sensing and logging of the tank level.
APPLICATION -
Tank Level Monitor w/Alarm and Loss-of-Weight Fill
MODEL INFORMATION
Parameter Value
INP1
1.728 mV
dSP1
1,000 ltr
INP2
20.750 mV
dSP2 10,000 ltr
Product Product Name Product Number
Weight Indicator (85 - 250VAC Power) MP30/00 9408-800-30001
Weight Indicator (24V Power) MP30/01 9408-800-30011
Quad Relay Option Card
Dual Relay Option Card
MP30/10
MP30/11
9408-800-30101
9408-800-30111
Linear Output Option Card MP30/20 9408-800-30201
RS232 Comm Option Card MP30/31 9408-800-30311
RS485 Comm Option Card MP30/32 9408-800-30321
DeviceNet Comm Option Card MP30/40 9408-800-30401
PC Set-up Software MP30/50 9408-800-30501