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MM1200
THERMOCOUPLE INPUT
SINGLE LIMIT ALARM

FEATURES
bullet Provides a DPDT Relay Contact Closure at a Preset Thermocouple Input
bullet Cold Junction Compensated
bullet Standard Fail-safe Operation
bullet Red and Green LED Alarm Status Indicators
bullet Adjustable Deadband
bullet Latching Alarm Available (MM1210)
bullet 4 mV Minimum Input Span
bullet Unlimited* Choice of Input/Output Ranges
bullet Upscale Burnout Protection (Downscale Available)
bullet Choice of Power Options
bullet 10 + 5 Year Warranty


DESCRIPTION

The MM1200 monitors any thermocouple input signal 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 the 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 must be momentarily interrupted to reset the alarm.

Cold junction compensation is provided by a solid state temperature sensor embedded in the thermocouple terminal strip.  The module includes filtering and conditioning to reduce susceptibility to transients and noisy operations.

Upscale burnout protection is provided as standard. In the event the thermocouple opens, the module behaves as though the input goes offscale high. Option B provides downscale burnout protection (module behaves as though the input goes low).

TYPICAL APPLICATIONS

Heater/cooler control, HI/LO temperature alarm.

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 a 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 socket is available (HKB-HK2D-11).  A DIN rail mounted socket (P/N DMP011)  is available for 35mm symmetrical rail.

SPECIFICATIONS

INPUT RANGE
 select any type TC
 (min span 4 mV)

SETPOINT
0 to 100% of span

DEADBAND
0.5% to 100% of span

RESPONSE TIME
20 ms typical
  (range dependent)

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


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