Robertshaw 158A User Manual

MODEL 158A 909GF197B

INSTRUCTION MANUAL

MODEL 158A

LEVEL-TEL

FOR

We do our level best

Industrial Products Division
1602 Mustang Drive
Maryville, Tennessee 37801
Phone: [phone] Fax: [phone]

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Probe, Cable and Conduit Outlet Box
shown for illustration only.
Must be ordered separately.

INSTRUCTION MANUAL NUMBER

909GF197B

P-2410

MODEL 158A 909GF197B

Section I – DESCRIPTION

1.1 GENERAL

The Robertshaw Model 158A Level-Tel is a
capacitance operated DC current transmitter with
noninteracting and independent zero and span
adjustments internally located. The transmitter is
remotely mounted from the probe with a triax
cable interconnected between the probe and the
transmitter.

1.2 MODEL IDENTIFICATION
Identify instrument models in accordance with the

descriptions and variations listed in each table.

158A - B 1 - A 1

Key Model No.
Table 1 – Output Current
Table 2 – Supply Voltage
Table 3 – Display Housing and Indication
Table 4 – Alarm Options

KEY MODEL NO.

Model

No.

158A Capacitance-to-current transmitter

system for remotely mounted probe
assemblies. Control Unit is
available with or without indication
and optional alarms.

Table 1 – OUTPUT CURRENT

Desig. Description

A 1-5 mADC
B 4-20 mADC
C 10-50 mADC
D 0-10 mADC

Table 2 – SUPPLY VOLTAGE

Desig. Description

1
2
3

26.5 VDC, ± 10%
120 VAC, ± 10%, 50/60 Hz
240 VAC, ± 10%, 50/60 Hz

Description

¾ May only be used with Designation E on
Table 3.

Table 3 – DISPLAY HOUSING AND

INDICATION

Desig. Description

A Water tight enclosure without

indicator.
Meets NEMA Type 4 and CSA
Enclosure 5.

B Water tight housing with indicator.

Meets NEMA Type 4 and CSA
Enclosure 5.

C Explosion proof housing without

indicator.
For Class I, Division 1, Groups C
and D; Class II, Division 1, Groups
E, F and G, areas.

D Explosion proof housing with

indicator.
For Class I, Division 1, Groups C
and D; Class II, Division 1, Groups
E, F and G, areas.

E Large weatherproof enclosure with

indicator to be used with optional
alarms.
Meets NEMA Type 12 & 13 and
CSA Encl 3.

Table 4 – ALARM OPTIONS

Desig. Description

1 None
2 ¾Alarm Relays for High or Low

Alarm.

3 ¾Alarm Relays for High and Low

Alarms.

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MODEL 158A 909GF197B

1.3 TRIAXIAL CABLE ACCESSORY ITEMS

032KE03X-XX¾
GENERAL PURPOSE (polyethylene insulated)
Triax Cable with probe connection conduit
outlet box. (Recommended for use with
customer supplied rigid or flexible conduit.)
Maximum temperature 185° F.

032KE05X-XX¾
GENERAL PURPOSE (polyethylene insulated)
Triax Cable in flexible conduit (protective
armor) with probe connection conduit outlet
box. Maximum temperature 185° F.

032KE04X-XX¾
HIGH TEMPERATURE (Teflon insulated) Triax
Cable with probe connection conduit outlet box.
(Recommended for use with customer supplied
rigid or flexible conduit.) Maximum
temperature 350° F.

032KE06X-XX¾
HIGH TEMPERATURE (Teflon insulated) Triax
Cable in flexible conduit (protective armor) with
probe connection conduit outlet box. Maximum
temperature 350° F.

032KE090-05 (5 ft long)

032KE090-10 (10 ft long)
GENERAL PURPOSE (polyethylene insulated)
Triax Cable in explosion proof flexible conduit
(protective armor) with seal fitting and probe
connection conduit outlet box. Maximum
temperature 185° F.

032KE100-05 (5 ft long)

032KE100-10 (10 ft long)
HIGH TEMPERATURE (Teflon insulated) Triax
Cable in explosion proof flexible conduit
(protective armor) with seal fitting and probe
connection conduit outlet box. Maximum
temperature 350° F.

¾ Substitute length in feet for X-XX in part
number.

Example: For 10 feet substitute 0-10

For 120 feet substitute 1-20

Explosion proof cables are standard in 5 and
10 foot lengths.

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MODEL 158A 909GF197B

Section II - SPECIFICATIONS

2.1 ENVIRONMENTAL

Ambient Temperature Limits.......-40° F to +160° F

Vibration Limits................± 2 G from 10 to 200 Hz

2.2 ELECTRICAL

Supply Voltage............. 120 VAC ± 10%, 50/60 Hz

240 VAC ± 10%, 50/60 Hz

26.5 VDC ± 10%

2.4 ENCLOSURE

Water Tight ...............NEMA 4, CSA Enclosure 5,

Polyurethane painted cast aluminum

Explosion Proof...Class I, Division 1, Groups C, D;

Class II, Division 1, Groups E, F, G;

Polyurethane painted cast aluminum

Weatherproof..... NEMA 12, 13, CSA Enclosure 3,

Polyurethane painted steel

2.5 INTRINSIC SAFETY

Models 158A – (A, B) (1, 2) – (A, B, C, D) – 1:

Supply Power........................... 5 watts, 7 VA max.

Terminal Capacitance Range............ 0 to 1000 pF

Probe circuit is CSA Certified intrinsically
safe for Class I, Division 1, Group C & D;
Class II, Division 1, Group E, F & G

Span Capacitance Range........ 10 pF plus 1 pF for

each 10 feet of Triax

cable up to 2000 pF

Maximum Recommended

Terminal/Span Ratio....................................... 10:1

Output Signal

and Load...................1-5 mADC into 0-2500 ohms

4-20 mADC into 0-700 ohms
10-50 mADC into 0-250 ohms
0-10 mADC into 0-1000 ohms

hazardous locations when connected as
shown on drawing 907GA518 (Figure 8).

2.6 AGENCY CERTIFICATIONS

Models 158A – (A, B) (1, 2) – (A, B, C, D) – 1:

CSA Certified .............................File LR 18690

Connecting Cable Length.................150 feet max.

2.3 PERFORMANCE

Linearity.................................. 0.5% max. for span

less than 1000 pF

1% max. for span

greater than 1000 pF

Repeatability...............................................± 0.1%

Sensitivity......................................0.01% minimum

Frequency Response.........................-3 db at 1 Hz

Supply Variation Effect ...............0.5%/10% supply

Ambient Temperature Effect:

Span................................................0.01%/° F

Zero............................. 0.01%/F or 0.01 pF/F,

whichever is greater

Output Signal Ripple............................. 0.2% max.

Output Meter Accuracy.................................. ± 2%

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MODEL 158A 909GF197B

Section III - INSTALLATION

3.1 GENERAL

Examine the instrument for possible shipping
damages. IMPORTANT: If for any reason it is
determined that parts should be returned to the
factory, please notify the nearest Robertshaw
sales representative prior to shipment. Each unit
must be properly packaged to prevent damage.
Robertshaw assumes no responsibility for
equipment damaged in shipment due to improper
packaging.

Choose the location in accordance with good
instrument practice, avoiding extremes of
temperature, humidity and vibration (see
Specifications, Section II).

3.2 PROBE MOUNTING

3.3 TRANSMITTER UNIT MOUNTING

The Model 158A is designed for vertical surface
mounting: e.g. wall, panel or column. Choose the
mounting location to avoid extremes of ambient
temperature or vibration (see Specifications,
Section II).

3.4 WATER TIGHT & WEATHERPROOF
TRANSMITTER MOUNTING & ELECTRICAL
CONNECTIONS

See Figures 1, 3, 4, 5, 6 and 7 for the mounting
dimensions and electrical connections of the
Water Tight and Weatherproof Transmitters. See
Figure 8 for interconnection diagram for those
models certified for intrinsically safe probe
installations.

3.5 EXPLOSION PROOF TRANSMITTER
MOUNTING & ELECTRICAL CONNECTIONS

Level-Tel probes for use with the Model 158A are
purchased separately from a variety of styles and
types which provide for various specific
applications involving liquids or granular
materials. Insulated rod-type probes are normally
used for liquid solutions or liquid-interface
junctions.

Since many materials have a tendency to build up
on the probe over extended periods of operation,
it is advisable on horizontally mounted probes to
place the probe so that its lower tip is below the
gland entrance. This encourages self-cleaning by
permitting the material to drip from the probe.
However, some materials will continue to build up
and cause the Level-Tel to become insensitive or
fail to operate. If such material is being used, the
installation should be made so that the probe is
easily removed for periodic cleaning.

The face of the gland on the rod-type probes
must be installed until nearly flush with the vessel
wall. DO NOT install the probe in a nozzle,
recess, or open-end well, unless the probe was
supplied with a factory assembled sheath as
there is danger of material collecting in such a
recess and causing false operation.

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See Figures 2, 3 and 5 for the mounting
dimensions and electrical connections of the
Explosion Proof Transmitter. See Figure 8 for the
interconnection diagram for those models certified
for intrinsically safe probe installations.