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MM1220 Thermocouple Input Dual Limit Alarm
 Description
The MM1220 monitors any thermocouple input signal and provides two sets of spdt, 5 A alarm relays with two independently adjustable setpoints. Each setpoint has a set of red/green LEDs to indicate alarm status. When the input is between the setpoints, the relays are normally de-energized. When the signal exceeds a particular setpoint, the relay becomes energized. To provide a fail-safe
operation (loss of power resulting in alarm state), select Option R. The module can be supplied as a HI/HI, HI/LO, or LO/LO alarm (HI/LO supplied if not specified).
Standard deadband on both alarms is fixed at 0.5% of span. (Option A provides adjustable deadband of 0.5% to 100% of span.) Option D, latching alarms, 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.
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).
Download MM1220 Brochure
Download MM1220 Manual
Features
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Provides Relay Contact Closures at Preset Thermocouple Input
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Cold Junction Compensated
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Fail-safe, Latching, and Adjustable Deadband Available
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Red and Green LED Alarm Status Indicators
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4 mV Minimum Input Span
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Unlimited* Choice of Input Ranges
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Upscale Burnout Protection (Downscale Available)
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Choice of Power Options
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10 + 5 Year Warranty
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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). The sockets are molded plastic suitable for mounting on a flat surface. The MP011 will mount in 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 (MP011) is available for 35mm symmetrical Din rail.
Specifications
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INPUT RANGE
select any type TC
(min span 4 mV)
SETPOINT
Each alarm
0 to 100% of span
DEADBAND
Standard
Fixed
0.5% of span
(Option A)
0.5% to 100% of span
RESPONSE TIME
20 ms typical
WR < = 200 ms
(range dependent)
ACCURACY
±0.01% of span
COMMON MODE REJECTION
120 dB, DC to 60 Hz
RELAY CONTACTS
2 (spdt)
Resistive Load:
5 A max, 150 W max
220 VAC max, 30 VDC max
Inductive Load
1/8 HP max at 120/240 VAC
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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 + 30 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
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CONNECTIONS
Power, AC L1 or DC +
Power, AC L2 or DC -
T/C + Input
T/C - Input
Relay 1 NO
Relay 1 C
Relay 1 NC
Relay 2 NO
Relay 2 C
Relay 2 NC
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PINS
1
3
T/C Terminal +
T/C Terminal -
6
7
8
9
10
11 |
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