United Electric Controls J120, J120K, H121K, H121, H122 Installation And Maintenance Instructions Manual

IMP120-17

120 Series
Explosion-Proof Pressure and
Differential Pressure Switches

Types
J120, J120K, H121, H121K, H122, H122K

UNITED ELECTRIC
CONTROLS

Installation and Maintenance
Instructions

Please read all instructional literature carefully and thoroughly before starting. Refer to the final page for the listing of Recommended
Practices, Liabilities and Warranties.

GENERAL

MISUSE OF THIS DEVICE MAY CAUSE EXPLOSION AND
PERSONAL INJURY. THESE INSTRUCTIONS MUST BE

THOROUGHLY READ AND UNDERSTOOD BEFORE DEVICE IS

INSTALLED.

THIS DEVICE IS SUITABLE FOR USE IN CLASS I, DIVISION 1,

GROUPS B, C AND D; CLASS II, DIVISION 1, GROUPS E, F AND
G; CLASS III

ENCLOSURE TYPE 4X, 7 & 9.

The device has been certified in accordance with the
applicable requirements of the following standards:

• IEC 60079-0, 6

• IEC 60079 -1, 7

• IEC 60079 -1, 6

• IEC 60079-31, 2

• EN 60079-0:2012+A11:2013

• EN 60079-1:2007

• EN 60079-31:2014

THIS DEVICE IS ATEX CERTIFIED FOR EQUIPMENT CATEGORY

2. SUITABLE FOR APPROPRIATE USE IN GAS ZONE 1 & DUST
ZONE 21 APPLICATIONS.

0539 IECEx UL 03.0001X

II 2 G Ex db IIC T6 Gb
II 2 D Ex tb IIIC T85°C Db IP66

-40°C≤Tam b.≤+75°C

BEFORE INSTALLING, CHECK THE SENSOR MODEL SELECTED
FOR COMPATIBILITY TO THE PROCESS MEDIA IN CONTACT
WITH THE SENSOR AND WETTED PARTS.

; OR NON-HAZARDOUS LOCATIONS ONLY.

th

Edition, Revision Date 2013/12

th

Edition, Revision Date 2014/06

th

Edition, Issue Date 2007/04

nd

Edition, Issue Date 2013 /11

DEMKO 09 ATEX 0815573X

*Proof Pressure: The maximum pressure to which a pressure sensor

may be occasionally subjected, which causes no permanent damage
(e.g., start-up testing). The unit may require re-gapping. (See Part
II- Adjustments)

**Over Range Pressure: The maximum pressure to which a pressure

sensor may be continuously subjected without causing damage and

maintaining set point repeatability.

***Working Pressure Range The pressure range within which two

opposing sensors can be safely operated and still maintain set point

repeatability.

THIS DEVICE DOES NOT HAVE ANY FIELD REPLACEABLE

PARTS. ANY SUBSTITUTION OF COMPONENTS MAY IMPAIR
SUITABILITY FOR CLASS I, DIVISION 1.

The 120 Series pressure and differential pressure switches are
actuated when a bellows, diaphragm or piston sensor responds to
a pressure change. This response at a pre-determined set point(s)
actuates a SPDT, DPDT or dual SPDT snap-acting microswitch(es),

which convert the pressure signal into an electrical signal. Control

set point(s) may be varied by turning the internal adjustment hex
(J120 & J120K models) or the external knob and pointer(s) (H121,
H121K, H122, & H122K models, see picture above) according to the

procedures outlined. (See Part II - Adjustments)

Please refer to product bulletin for product specifications. Product

bulletins may be found at www.ueonline.com.

UE declarations and third party issued certifications are available for

download at www.ueonline.com/prod_approval.

Date code format on nameplate is “YYWW” for year and week.

TO PREVENT IGNITION OF HA ZARDOUS ATMOSPHERES,

DISCONNECT SUPPLY CIRCUITS BEFORE OPENING. KEEP

COVER TIGHT WHILE CIRCUITS ARE ENERGIZED.

PROOF PRESSURE* LIMITS STATED IN THE LITERATURE
AND ON NAMEPLATE MUST NEVER BE EXCEEDED, EVEN BY

SURGES IN THE SYSTEM. OCCASIONAL OPERATION OF DEVICE
UP TO MAXIMUM PRESSURE IS ACCEPTABLE (E.G., START-UP, TESTING).
CONTINUOUS OPERATION SHOULD NOT EXCEED THE DESIGNATED
OVER RANGE PRESSURE** OR WORKING PRESSURE RANGE***.

Part I -Installation

Tools Needed–Screwdriver/Adjustable Wrench to 1-1/2”

MOUNTING

IMP120-17

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TO PREVENT ELECTROSTATIC DISCHARGE, WIPE DOWN COVER
AND ENCLOSURE OF ANY DUST BUILD UP BEFORE REMOVING
COVER.

INSTALL DEVI CE WHERE S HO CK , VIB RATION AND

TEMPERATURE FLUCTUATIONS ARE MINIMAL. DO NOT MOUNT

DEVICE IN AMBIENT TEMPERATURES THAT EXCEED THE
LIMITS ON THE NAMEPLATE FOR THE APPROPRIATE AREA

MOUNT DEVICE TO PREVENT MOISTURE FROM ENTERING

THE ENCLOSURE. IT IS IMPERATIVE TO USE PROPERLY RATED

EXPLOSION-PROOF SEALING FITTINGS FOR ELECTRICAL WIRE
ENTRY.

TO PREVENT IGNITION OF HAZARDOUS ATMOSPHERES, SEAL

CONDUIT RUNS WITHIN 18 INCHES OF ENCLOSURE

TYPE J120 IS PROVIDED WITH TWO 3/4” NPT ELECTRICAL
CONDUIT OPENINGS, EITHER OF WHICH OR BOTH CAN BE

USED DURING INSTALLATION. A 3/4” EXPLOSION-PROOF
PLUG* IS PROVIDED FOR PROPERLY PLUGGING THE UNUSED CONDUIT
OPENING. THE EXPLOSION PROOF PLUG MUST BE PROPERLY
INSTALLED.

*Plug is approved explosion-proof with the device as a full assembly and

does not carry individual markings.

THE CONNECTION OF THE DEVICE SHALL BE MADE BY CABLE

ENTRIES OR A STOPPING BOX SUITABLE FOR THE CONDITIONS

OF USE AND CORRECTLY INSTALLED, AND CERTIFIED BY TYPE

OF EXPLOSION PROTECTION - FLAMEPROOF ENCLOSURE ‘d’.

ALWAYS HOLD A WRENCH ON THE PRESSURE HOUSING HEX

WHEN MOUNTING THE DEVICE. DO NOT TIGHTEN BY TURNING

THE ENCLOSURE AS THIS WILL DAMAGE SENSOR AND WEAKEN

SOLDER AND WELDED JOINTS.

VERTICAL MOUNTING (PRESSURE CONNECTION FACING DOWN,
SEE FIGURE 1A) IS RECOMMENDED; HOWEVER DEVICE CAN
BE MOUNTED IN ANY ORIENTATION WITH ADHERENCE TO
PREVIOUS WARNINGS AND EXCEPTIONS BELOW.

Differential Pressure Types J120K, H121K, H122K
Opposed Sensor Models 36-39, (S)147(B)-(S)157(B), 367

“Opposed sensor” differential pressure switches should be mounted

with their pressure connection in the horizontal position (See Figure

2). This will properly orient the 1/4” NPT venting conduit at the
bottom of the middle compartment (standardly supplied with plastic
plug).

Figure 2

Opposed Sensor Models

Device with Manual Reset (Option 1530)

On models supplied with an external manual reset button, be sure to
leave sufficient finger space over the reset button for the operator to
reset the control.

Figure 1A:

H121, H121K, H122, H122K

Mount device vertically (pressure connection facing down, see Figure

1A) or horizontally (see Figure 1B). Device may be surface mounted via

the four 1/4” screw holes on the enclosure or mounting bracket. It can
also be mounted directly to a rigid pipe using the pressure connection.

Type J120, J120K Models 520-525, 530-535

It is recommended that models 520-525 and 530-535 be mounted
vertically (pressure connection facing down, see figure 1A). If
horizontal mounting (see figure 1B) or vertical mounting (pressure
connection facing up) is required, set-point may shift (particularly
models 523, 533) and set-point adjustment is recommended. Consult
factory for additional information

Device with Breather Drain (Option M450)

Type J120, J120K Models 455-559

Mount with breather drain facing down (See Figure 1B). The conduit
connection must be “potted” for this type of installation.

Types H121, H122 & H122P, All Models

Mount in vertical position with pressure assembly and breather drain
facing down (See Figure 1A).

Figure 1B

J120, J120K

IMP120-17

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WIRING

DISCONNECT ALL SUPPLY CIRCUITS BEFORE WIRING DEVICE.
WIRE DEVICE IN ACCORDANCE WITH LOCAL AND NATIONAL
ELECTRICAL CODES. MAXIMUM RECOMMENDED WIRE SIZE IS

14 AWG AND RECOMMENDED TIGHTENING TORQUE FOR FIELD WIRING

TERMINALS IS 7 TO 17 IN-LBS

ELECTRICAL RATINGS STATED IN LITERATURE AND ON NAME­PLATE MUST NOT BE EXCEEDED—OVERLOAD ON A SWITCH
CAN CAUSE FAILURE ON THE FIRST CYCLE.

FIELD WIRING MUST BE RATED 90°C MINIMUM. FOR AMBIENT

TEMPERATURES BELOW -10°C, USE SUITABLE FIELD WIRING.

THE EXTERNAL GROUNDING TERMINAL IS NOT TO BE USED
AS THE PRIMARY EQUIPMENT GROUNDING TERMINAL. THE

INTERNAL GROUNDING TERMINAL SHALL BE USED AS THE

PRIMARY EQUIPMENT GROUNDING MEANS AND THE EXTERNAL
GROUNDING TERMINAL IS ONLY FOR A SUPPLEMENTAL (SECONDARY)
GROUNDING CONNECTION WHERE LOCAL AUTHORITIES PERMIT OR

REQUIRE SUCH A CONNECTION.

TO PREVENT SEIZURE OF ENCLOSURE COVER, DO NOT

REMOVE LUBRICANT. THREADS SHOULD ALSO BE FREE OF

DIRT, ETC.

Remove cover and wire device (See Figure 3). Wire directly to the
terminal block. An internal grounding terminal is located near the
right-hand conduit opening. Replace cover and hand tighten to fully

engage cover O-ring.