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MM1800
POTENTIOMETER POSITION INPUT
SINGLE LIMIT ALARM

FEATURES
bulletProvides a DPDT Relay Contact Closure at a Preset Potentiometer Position Input
bulletPotentiometer Values from 100 ohms to 100 kilohms
bulletStandard Fail-safe Operation
bulletRed and Green LED Alarm Status Indicators
bulletAdjustable Deadband
bulletLatching Alarm Available (MM1810)
bulletUnlimited* choice of Input Ranges
bulletChoice of Power Options
bullet10 + 5 Year Warranty


DESCRIPTION

The MM1800 monitors the slide position of a potentiometer and trip 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 operations. It also utilizes a stable 1 V power supply to excite the potentiometer.  Any value potentiometer from 100 ohms to 100 kilohms can be used.

TYPICAL APPLICATIONS

Tank level, valve or actuator 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 socket is available (HKB-HK2D-11).  A DIN rail mounted socket (P/N DMP011) is available for 35mm symmetrical rail.

SPECIFICATIONS

INPUT POTENTIOMETER RESISTANCE
 any value from 100 ohms to 100 kilohms

INPUT SPAN ADJUSTMENT
70% to 100% of pot rotation

INPUT OFFSET ADJUSTMENT
0 to 25% of pot rotation

INPUT IMPEDANCE
>10 megohms

EXCITATION
1 V, 10 mA max load

SETPOINT
0 to 100% of span

DEADBAND
0.5% to 100% of span

RESPONSE TIME
20 ms typical

ACCURACY
±0.1% of span

COMMON MODE REJECTION
120 dB, DC to 60 Hz

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

TEMPERATURE STABILITY
±0.02% of span/°C max

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

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 -
Potentiometer Excitation
Input +
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
2
4
5
6
7
8
9
10
11