Scope of supply ...................................................................................................................................... 5
Function .................................................................................................................................................5
Checking the assignment of the switching functions ............................................................................16
Operation
ER 50-1, ER 56-1 ..................................................................................................................................16
Water level limiter ................................................................................................................................ 16
Troubleshooting
Fault finding list .................................................................................................................................... 17
3
4
Important Notes
Usage for the intended purpose
The level electrodes ER 50-1 and ER 56-1 are designed for signalling liquid levels.
Safety note
The equipment must only be installed and commissioned by qualified and competent staff.
Retrofitting and maintenance work must only be performed by qualified staff – who through adequate
training – have achieved a recognised level of competence.
Danger
When loosening the electrode steam or hot water might escape.
This presents the danger of severe scalds to the whole body.
Before removing the electrode make sure that the boiler pressure is zero bar.
The electrode becomes hot during operation. Touching the hot equipment presents the
risk of severe burns to hands and arms. All installation and maintenance work must only
be performed when the equipment is cold.
Attention
The name plate specifies the technical features of the equipment. Note that any piece of
equipment without its specific name plate must neither be commissioned nor operated.
ATEX (Atmosphère Explosible)
According to the European Directive 94/9/EC the equipment must not be used in potentially explosive
atmospheres.
Explanatory Notes
Scope of supply
ER 50-1
1 Level electrode ER 50-1
1 Joint ring D 33 x 39 DIN 7603-1.4301
1 Installation manual
ER 56-1
1 Level electrode ER 56-1
1 Joint ring D 33 x 39 DIN 7603-1.4301
1 Installation manual
Description
The level electrodes ER 50-1 and ER 56-1 work according to the conductivity measurement principle.
The ER 50-1/56-1 can signal a maximum of three levels in electrically conductive liquids:
■ Low level alarm (MIN alarm), pump ON, pump OFF with one NO contact
ER 50-1 for vessels up to PN 6, e. g. for condensate and low-pressure systems as well as (pressurised)
hot-water installations, concrete vessels, feedwater tanks. PN 6 flanges only available on request.
ER 56-1 for vessels up to PN 40, e. g. in high-pressure steam plants.
For the operation of the level electrodes ER 50-1 and ER 56-1 an external GESTA level switch is
required, e. g. NRS 1-1 for fill and discharge control with first low-level alarm, NRS 1-5 for fill and
discharge control with high-level alarm, NRS 1-2 as first low-level alarm and high-level alarm or NRS
1-3 as water level limiter with test button.
Function
The conductivity of the liquid is used to signal the liquid level. Some liquids are conductive, which
means that they allow an electric current to flow through them. For the safe functioning of this device
a minimum conductivity of the liquid to be monitored is required.
The conductivity measurement method can detect two conditions: electrode rod submerged or
exposed, meaning switchpoint reached (or exceeded) or not yet reached. Before installation, the
length of the electrode rod must be cut to the required switching levels, e. g. for limit alarm or the
switching of a valve or pump.
Design
ER 50-1: Screwed 1" to EN ISO 228-1, PN 6
ER 56-1: Screwed 1" to EN ISO 228-1, PN 40
5
6
Technical Data
ER 50-1, ER 56-1
Type approval
TÜV · WR/WB · 03-302
Service pressure
ER 50-1: 6 bar g at 159°C
ER 56-1: 32 bar g at 238°C
0.5 μS/cm, depending on level switch NRS 1-...
Electrical connection
Four-pole connector, cable gland M 16
Protection
IP 65 to EN 60529
Max. admissible ambient temperature
70 °C
Weight
Approx. 0.8 kg
1.4571 CrNiMoTi17-12-2
PTFE
–1
Corrosion resistance
Provided that the equipment is used for its intended purpose, its safety is not impaired by corrosion.
Sizing
The body must not be subjected to sharp increases in pressure. Welds and flanges of the electrode are
designed to withstand dynamic loading (bending and alternating stress). The dimensional allowances
for corrosion reflect the latest state of technology.
Technical Data – continued –
Name plate / marking
Equipment designation
Fig. 1
Fig. 2
7
8
Technical Data – continued –
Dimensions
270
∅ 42
1" to EN ISO 228-1
1000, 1500
Fig. 3
Design
ER 50-1, ER 56-1
1
50
Fig. 4
4
3
2
∅ 40
1" to EN ISO 228-1
N 10
≥ 14
65-70
N 8
Fig. 5
0.5
9
10
Functional Elements
MAX 70°C
MAX 95%
%
IP 65
ER 50-1, ER 56-1
5
6
7
8
9
0
Fig. 6
!
"
Design / Functional Elements – continued –
Key
1 Thermal insulation, provided on site, d = 20 mm (outside of thermal insulation of
steam generating unit)
2 Seating surface
3 Joint ring D 33 x 39 to DIN ISO 7603 – 1.4301
4 Electrode thread 1" to EN ISO 228-1
5 Screw M4
6 Cover
7 Upper part of terminal box
8 Connecting plate
9 Sealing element
0 Contact plate for level electrode
! Cable clamp
" Cable gland M 16 (PG 9)
11
12
Installation
ER 50-1, ER 56-1
1. Determine required measuring lengths of the electrode tips and enter data in the
table “Functions”,
Fig. 4.
2. Cut electrode tips
1 , 2 , 3 and 4 accordingly.
3. Deburr faces of electrode tips.
4. Strip off 50 mm of PTFE insulation from the ends of the electrode tips.
5. Check seating surfaces of threads or flange provided on vessel or boiler standpipe,
6. Place joint ring
3 onto seating 2 of the electrode, Fig. 4.
Fig. 5.
Use only joint ring (of stainless steel 1.4301) D 33 x 39 to DIN 7603 supplied with electrode.
7. Apply a light smear of silicone grease (e. g. DOW Corning 111 Compound) to electrode thread
4.
8. Screw level electrode into threads or flange provided on vessel or boiler standpipe and tighten with a
41 mm open-end spanner. The torque required is 140 Nm when cold.
Table “Functions”
FunctionFunctionElectrode tipLength [mm]
Reference electrode1
e. g. pump OFF2
e. g. pump ON3
e. g. high-level alarm4
Please enter data.
Attention
■
The seating surfaces of the threads or flange provided on the vessel or boiler standpipe
must be accurately machined, Fig. 5.
■
Do not bend electrode tips when mounting.
■
Do not include electrode body in the thermal insulation of the boiler.
Note
■
For the approval of the boiler standpipe with connecting flange the relevant local and
national regulations must be considered.
■
See four examples of installation on page 13.
Tools
■
Open-end spanner 41 mm A. F.
■
Bolt cutter
■
Hacksaw
■
Flat file, medium cut
Installation – continued –
Examples of installation
Fig. 7
&
=
≤90°
∅ 20
¾" BSP
1" BSP
DN 50
∅ 20
1" BSP
1" BSP
§
$
%
20
≤ 1500
DN 50
&
/
(
b
≥ 10
c
Fig. 8
≤90°
∅ 20
1" BSP
§
$
20
∅
20
/
(
b
c
§
$
DN 20
≤ 20
&
§
$
a
%
DN 100
24.5 24.5
≤ 3000
/
)
Centre distance
/
b
=
4
20
∅ 20
DN 20
≤ 20
b
≤90°
∅ 20
d
Fig. 10Fig. 9
DN 20
13
14
Installation – continued –
Key
Flange PN 40, DN 50, DIN 2527
§
Flange PN 40, DN 100, DIN 2527
For the approval of the boiler standpipe with connecting flange the relevant regulations
$
must be considered.
Vent hole
%
High water (HW)
&
Electrode tip ∅ = 5 mm
/
Protection tube DN 80
(
Protection tube DN 100
)
Electrode distance ≥ 14 mm
=
Electrode distance ≥ 40 mm
a
Low water (LW)
b
Reducer DIN 2616, part 2 K-88.9 x 3.2 – 42.4 x 2.6 W
c
Reducer DIN 2616, part 2 K-114.3 x 3.6 – 48.3 x 2.9 W
d
Electrical Connection
ER 50-1, ER 56-1
Wiring via four-pole connector.
Screened four-core cable, e. g. I-Y(St)Y 2 x 2 x 0.8 or LIYCY 4 x 0.5 mm².
Max. length 100 m with conductivities from 10 μS/cm.
Max. length 30 m with conductivities from 0.5 μS/cm.
Max. length 15 m with conductivities from 0.5 μS/cm and application of the ancillary unit URN 1
(24 V DC).
1. Loosen screw
2. Take the terminal box off the level electrode, leaving the sealing element
3. Remove cover
4. Press connecting plate
The upper part of the terminal box can be turned in steps of 90°.
5. Detach cable gland and cable clamp
6. Run cable through cable gland
connecting plate 8 according to the wiring diagram.
7. Press connecting plate
8. Hold cable with cable clamp
9. Mount cover
10. Put upper part of the terminal box onto the level electrode and fix it firmly with screw
Wiring diagram
5, Fig. 6.
6.
8 out of the upper part of the terminal box 7.
! from the upper part of the terminal box 7.
" and upper terminal box 7 and connect the terminals of the
8 into the upper part of the terminal box and align the cable.
! and cable gland " in position.
6 and insert screw 5.
9 on the contact plate 0.
5.
Fig. 11
Tools
■
Screwdriver for cross-recess head screws, size 1
■
Screwdriver for slotted screws, size 2.5, completely insulated according to DIN VDE 0680
■
Open-end spanner 17 mm A. F.
15
16
Commissioning
Checking electrical connection
1. Make sure that the system ER 50-1/ ER 56-1 has been wired in accordance with the wiring diagram,
Fig. 11.
2. Make sure that the mains supply corresponds to the wiring carried out on the equipment.
Checking the assignment of the switching functions
1. Check the switching function “High Level Alarm (HW)” of the electrode tip 4 .
For this purpose raise the water level in the vessel above the high water mark. As soon as the water
exceeds the high level mark the level switch must trigger a high level alarm.
2. Check the switching functions “Pump ON” and “Pump OFF”,
see table “Functions”.
Operation
ER 50-1, ER 56-1
Operation in conjunction with level switch NRS 1-1 for fill and discharge control with first low level
alarm.
Operation in conjunction with NRS 1-5 for fill and discharge control with high-level alarm.
Operation in conjunction with NRS 1-2 as first low-level alarm and high-level alarm in (pressurised) hot
water and steam plants to TRD 401, TRD 602, TRD 604, EN 12952, EN 12953 or according to national
regulations.
Operation in conjunction with NRS 1-3 as water level limiter with test button for steam boilers up to
max. 0.5 bar or in feedwater or condensate tanks.
Water level limiter
Note
■
Should malfunctions occur during the commissioning procedure refer to chapter
“Troubleshooting” on page 17 in order to analyse and correct them.
Troubleshooting
Fault finding list
Level has exceeded switchpoint “High Water” – no function
Fault: Mains voltage has not been applied.
Remedy: Apply mains voltage. Wire equipment according to the wiring diagram.
Fault: The electric conductivity is too low.
Remedy: Use level switch with higher response sensitivity (0.5 μS/cm).
Fault: The electrode body does not have earth connection to the boiler.
Remedy: Clean seating surfaces and insert metal joint ring (of stainless steel 1.4301) to 33 x 39 to
DIN 7603. Do not insulate compact system with hemp or PTFE tape!
Level has fallen below switchpoint “Low Water” – no function
Fault: The electrode tips have earth connection.
Remedy: Change installation position.
Fault: The vent hole in the protection tube does not exist, is obstructed or flooded.
Remedy: Check protection tube and, if necessary, provide vent hole.
Fault: The isolating valves of the external measuring pot (optional) are closed.
Remedy: Open isolating valves.
Switchpoint has been reached – incorrect function
Fault:The switching function has not been correctly allocated. Electrode tips have been cut to the
wrong length.
Remedy: Identify electrode supply wire and reconnect accordingly.
If faults occur that are not listed above or cannot be corrected, please contact our service centre or
authorized agency in your country.