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MM1500
STRAIN GAUGE (BRIDGE) INPUT
SINGLE LIMIT ALARM

FEATURES
bulletProvides a DPDT Relay Contact Closure at a Preset Strain Gauge Bridge Input
bullet0.5 mV/V to 1 V/V Input Span
bulletStandard Fail-safe Operation
bulletRed and Green LED Alarm Status Indicators
bulletAdjustable Deadband
bulletLatching Alarm Available
bulletUnlimited* Choice of Input Ranges
bulletChoice of Power Options
bullet10 + 5 Year Warranty


DESCRIPTION

The MM1500 monitors the DC input signal from a strain gauge bridge and trips a dpdt, 5 A relay when the input exceeds the desired level. Normal operation has the relay energized for the non-alarm condition and de-energized for an alarm condition.  This provides a fail-safe alarm condition for loss of power to the module. The alarm has a set of red/green LEDs to indicate alarm status.

A deadband adjustment allows a deadband of 0.5% to 100% of span to be set into the module. The deadband is symmetrical about the setpoint.

With the latching option, the alarm has no deadband control.  Once the limit has been reached, the alarm latches and power to the module must be momentarily interrupted to reset the alarm.

The module includes filtering and conditioning to reduce susceptibility to transients and noisy operation. They also provide a well regulated excitation voltage for the strain gauge and a high quality differential preamplifier to condition the low level output from the bridge.

TYPICAL APPLICATIONS

Weight and pressure control, monitoring or warning.

MOUNTING

The module is designed to plug into a standard 11-pin relay socket.  Part number MP011 is a molded plastic socket suitable for mounting on a flat surface or 2 3/4 inch wide PVC snap track (TRK48).  Use CLP-1 hold-down clip if needed.  A Killark HK Series explosion-proof housing with dome and 11-pin sockets is available (HKB-HK2D-11).  A DIN rail mounted socket (P/N DMP011) is available for 35mm symmetrical rail.

SPECIFICATIONS

INPUT SPAN
0.5 mV/V to 1 V/V

EXCITATION
adjustable 4 V to 12 V
  40 mA max load

EXCITATION STABILITY
±0.005%/°C

SETPOINT
0 to 100% of span

DEADBAND
0.5% to 100% of span

RESPONSE TIME
<= 500 ms

ACCURACY
±0.1% of span

COMMON MODE REJECTION
120 dB, DC to 60 Hz

RELAY CONTACTS
1 (dpdt) **
Resistive Load:
  5 A max, 150 W max
  220 VAC max, 30 VDC max

Inductive Load
  (Power factor >= 0.4):
  2.5 A max, 75 W max
  220 VAC max, 30 VDC max

TRANSISTOR OUTPUT (Option V)
Relay driver
  (12 V coil, >= 220 ohms)
or open-collector outputs
  sink 100 mA, 30 V supply max

LINEARITY (Option T)
±0.01% of span

OPERATING TEMPERATURE
 14°F to 140°F
-10°C to  60°C

TEMPERATURE STABILITY
±(0.02% of span + 1.3 µ V)/°C max

POWER
115 VAC 10%, 50/60 Hz
  (2.5 W max)
230 VAC 10%, 50/60 Hz
  (2.5 W max)

DC Power Option
  24 VDC (limits 21-32 VDC)
  Isolation, DC power supply to input common
    10 megohms

 

* Within specified range limits

** Due to pins available, only one set of contacts are available for relay set #2.  Specify NO (Normally Open) or NC (Normally Closed).


CONNECTIONS
 Power, AC L1 or DC +
Power, AC L2 or DC -
Input +
Input -
Excitation +
Excitation -
Relay Set 1 NO
Relay Set 1 C
Relay Set 1 NC
Relay Set 2 NO or NC
Relay Set 2 C 		PINS
1
3
4
5
7
8
9
10
11
2
6