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Model 3770

 

DC STRAIN GAGE PANEL METER 

2    

C

O N N E C T I O N S

J1 – Shunt Command Connections.

 Connection is used to activate the positive or negative 

Shunt calibration command from the rear panel. When the + or – R CAL terminal is 
connected to LOGIC COM via a switch or relay, the installed Shunt resistor will be 
connected  Signal and + Sense or – Sense depending on the  Shunt polarity chosen 
and the CAL SENSE connection. CAL SENSE line is normally connected to + Signal for 
proper  signal  activation. 

Fig. 4

 SHUNT Command

Connections

J1 - SHUNT Activation 
Connections

Connecting LOG COMMON to the R CAL + or 
R CAL -  terminal will activate the installed 
shunt resistor (internal or external) across the 
connected four arm bridge sensor for 
simulated calibration & verification check of 
the sensor’s electrical characteristics. 

LOGIC COM

R CAL +

N/O 

Switch

J2 - HOLD & TARE Connections. 

Connection is used when external control of the "HOLD" 

or "TARE" features of the unit are enabled and are controlled by an external switch, PLC or 
relay. The LOGIC COM  signal is used to activate the analog HOLD or Analog TARE 
(offset) to the meter's display and analog output signals present on J3. 

Fig. 5

J1 Logic Controls

HOLD IN

     Activates Analog HOLD when connected to LOGIC COMMON

TARE IN

  

     Activates Analog TARE when connected to LOGIC COMMON

TARE ENABLE       

Enables remote TARE and disables front panel TARE when connected to LOGIC COMMON

LOGIC COMMON    

Connection to enable rear panel features

Push Button, Contact Relay, 

Switch…..

LOGIC COM 

HOLD

TARE

 TARE ENABLE

Page 

5

 

Summary of Contents for 3770

Page 1: ...MODEL 3770 DC STRAIN GAGE CONDITIONER SB 1 1 INSTRUCTION MANUAL 3700 Instrument Series...

Page 2: ...of the analog full scale signal The Model 3770 can be either calibrated by the two point dead weight process involving known input parameters or through the Shunt method using front panel push buttons...

Page 3: ...30 ppm C vs Time 10 ppm month Linearity better than 0 03 of full scale Filter 3 pole modified Butterworth 3 dB down at 2 Hz 20 Hz or 200 Hz selectable Fast output always enabled 5 KHz response J3 Pin...

Page 4: ...el Function J1 1 N C No connection J1 2 N C No connection J1 3 HOLD Input Analog Hold command J1 4 TARE Input Analog TARE command J1 5 TARE ENABLE External TARE enable input J1 6 LOGIC COM Logic Commo...

Page 5: ...nd a shorting wire in place of the external shunt resistor position This provides the electrical path for the Calibration Sense line to enable the sensor s internal shunt resistor when the or Shunt Ca...

Page 6: ...rnal or external across the connected four arm bridge sensor for simulated calibration verification check of the sensor s electrical characteristics LOGIC COM R CAL N O Switch J2 HOLD TARE Connections...

Page 7: ...KHz Analog Voltage Output 5 Vdc or 10 Vdc with front panel selectable cutoff filter 2 20 200 Hz Analog Current Output 4 20mA 4 12 20mA at selected cutoff filter SIGNAL SIGNAL SIGNAL SIGNAL SIGNAL SIGN...

Page 8: ...selects Display Full Scale Range Range will equate to an analog output value of 5 Vdc or 10 Vdc per Analog Control switch placement Selection is set for 1 count in 5000 2 counts in 10000 and 5 counts...

Page 9: ...range gain for 0 5 to 10 mV V sensors Display Span Adjustments Used to adjust the digital readout of the 3770 meter the user calibrates the analog output for a specific span value and then adjusts th...

Page 10: ...ion voltage The full scale analog output will be 5 000 Vdc The current output will be set for 4 ma zero and 20 ma will positive full scale The analog low pass filter will be set for 20 Hz Shunt calibr...

Page 11: ...nse leads of the bridge CAL Negative Calibration Activates the SHUNT Negative by switching in the external or internal shunt calibration resistor across the Cal Sense and Sense leads of the bridge TAR...

Page 12: ...t Note that changes in Span Gain will affect Zero Span and Zero re adjustments may need to be repeated to obtain the desired reading Note that the 3770 meter also has independent display adjustment ca...

Page 13: ...potentiometers fully CW Coarse is 22 turns Fine is 25 turns then reverse direction CCW Coarse 11 turns and Fine 13 turns to obtain mid authority of the controls Typically this is done on initial cali...

Page 14: ...scale analog output signal will be 5 VDC or 10 VDC as selected by the Analog Controls of the unit To accomplish the display adjustment change the user would first set the desired display range and dec...

Page 15: ...a factor of 2 Wide Span Position SPAN Low mV V SPAN High mV V 0 3 90 5 80 1 3 30 4 90 2 2 90 4 20 3 2 50 3 60 4 2 10 3 10 5 1 80 2 70 6 1 50 2 30 7 1 30 1 90 8 1 10 1 70 9 1 00 1 40 A 0 84 1 20 B 0 72...

Page 16: ...hase price to the Buyer ANY PRODUCT FOUND TO BE DAMAGED THROUGH CUSTOMER NEGLIGENCE OR MISUSE MAY BE EXCLUDED FROM ANY AND ALL POLICIES CONTAINED IN THIS DOCUMENT ALL EQUIPMENT TO BE REPAIRED OR REPLA...

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