NATIONAL CONTROLS NS156 User Manual

LIQUID LEVEL CONTROL SERIES

To Conductive

Tank

Probe

Typical Probe Connection

3.50

1.22 1.12

2.75

.37

WATER

SOLENOID

Input

Mounting Bracke

t

by Customer

To Probe

NS156

.25

P

1.40

L2

L1

Load

.22 Dia.

2 places

Probe

Terminal

Probe
Com

Com

P

(3673-3)

To Level Control

Voltage

Mounting

Holes

Common

Probe
Common

2-9

Resistance Sensors (Single Probe, Pump Up Logic with Time Delayed Output)

Models NS156 and NS159

FEATURES

100% functionally tested

●

Solid state sensing circuitry

●

Isolated UL Class ll sensing voltage

●

1/4” male fast-ons for circuit connection

●

Conformal coating to protect circuit

●

from harsh environments

●

Operating Logic: As liquid is removed from
a tank and contact with a probe is interrupt­ed, a fixed time delay is started. At the end
of the time delay, the output is activated
until the level rises and contacts the probe.
On Model NS159, when the output is
turned on, a fault timer is started. If the out
put is still on at the end of the fault time, the
fault timer will shut the output off until volt
age is removed and re-applied to the con
trol system. The purpose of the fault timer is
to eliminate overflow due to an open probe.
If the tank is non-conductive, a second
(common) probe must be installed at a level
where it will always be submerged.

File #E61377

SPECIFICATIONS

CONTROL TYPE

On/Off Resistance Sensing: Probe resistance

above set point activates fill output after a
fixed time delay

Sensing Voltage: 15 VAC, max. RMS
Sensing Current: 2 mA, max. RMS
Sensitivity Adjustment:

NS156: Factory set at 100 K ohms ±10%
NS159: Factory set at 500 K ohms ±10%

Activate Time Delay:

NS156: 5 sec. ±1 sec.
NS159: 1 sec. ±.5 sec.

Fault Timer Delay, NS159: 300 sec. ±15%

Contact factory for other sensitivity and time delay requirements.

INPUT

Operating Voltage: 120, 240 VAC, ±10%

-

Power Consumption: 3.0 VA max.
Frequency: 50/60 Hz

-

OUTPUT

-

Type:

NS156: Solid state switch, .75 A at 25°C, .34 A
at 77°C
NS159: Relay contact, 2 A at 120 VAC

Life:
NS156: 1,000,000 cycles min. at full load
NS159: 300,000 cycles min. at full load

PROTECTION

Isolation: 1500 VAC between probe and other

terminals
Transient Voltage: Protected by 30 joule metal

oxide varistor
Coating: Conformally coated with RTV to protect

against moisture

MECHANICAL

Terminations: 1/4” x .032” fast-ons
Mounting: 2 -.218” dia. holes

ORDERING INFORMATION

Pump Up 120 VAC LNC-NS156-120

Pump Up 240 VAC

Pump Up/Fault Timer 120 VAC

Probe Holder with Ground LLH-11383-010

Probe, 6” Long, 1/4” Dia., S.S.

Probe, 12” Long, 1/4” Dia., S.S.

Probe, 24” Long, 1/4” Dia., S.S.

Probe Assembly, Plastic Body LLP-001/2-011

AMETEK National Controls Corp. • 1725 Western Drive • West Chicago, Illinois 60185 • Tel: [phone] • 630-231-5900 • FAX: [phone] • www.nationalcontrols.com

LOGIC TYPE INPUT VOLTAGE PART NUMBER

ACCESSORY PART NUMBER

ENVIRONMENTAL

Operating Temperature:

NS156: +5°C to 77°C
NS159: +5°C to 65°C

LNC-NS156-240

LNC-NS159-120

LLP-06.00-OSS

LLP-12.00-OSS

LLP-24.00-OSS