Magnetic absolute encoder GEL 2037
General
Multiturn absolute rotary encoders with a resolution of up
to 25 bits in a compact designMagneto-resistive scanning of a diametral magnet pro-
vides unambiguous position values at every angular po-
sition via the SSI interfaceMagnetic scanning is not subject to ageing and is resist-
ant to temperature fluctuations, contamination or conden-
sation.Redundant position signal can be provided by integrated
resolver
Features
Total resolution 25 bits Absolute accuracy 0.8º Output signal SSI or SSI and resolver Magnetic gear
Advantages
Suitable for all standard applications and also for real
heavy-duty applicationsWithstands high shock/ vibration loads Not affected by dirt or oil mist Temperature behaviour stable over the long-term Full function in case of condensation:dew-point resistant! No ageing of the magnetic sensor technology
Fields of application
Construction machines Agricultural machines Food industry Wind power Offshore technology
Description
Construction and design
The encoder housing made of anodised aluminium has a flange dimension of 58 mm. The absolute rotary encoder
GEL 2037 is suitable for standard and heavy-duty applications, it also withstands aggressive media and impresses
with a long, maintenance-free service life.
The GEL 2037 is available with a heavy-duty flange or
clamping flange with tooth wheel adapter.
A very compact redundant system is realised by combination
with a resolver. The complete electrical isolation of the resolver from the magnetic absolute rotary encoder ensures
true redundancy of the absolute position values.
Sensing principle
The GEL 2037 is based on the contactless magnetic scanning of a diametral magnet. Magnetoresistive sensors measure
directly the absolute position within a turn and a magnetic gear supplies the number of turns.
The multiturn absolute rotary encoders in the GEL 2037 series provide an unambiguous position value for each angular
position with a resolution of up to 25 bits. In the process, the singleturn stages operate with a resolution of up to 13 bits.
The multiturn stage is based on a magnetic gear that saves the number of turns in a non-volatile form.
The magnetic absolute rotary encoder supplies the position
values in binary or gray code via a synchronous serial interface, (SSI).
The synchronous serial interface transfers the position data at a clock frequency of up to 1 MHz. Prior to further position
sampling, a minimum clock pulse space of 25 µs must be met.
Principle of the serial data transmission
gray code (25 bits), RS 422 / RS 485 standard
f | ≥ 40 kHz |
T | Length of the clock signal period (= 1/clock frequency) |
Tp | Clock pulse space, between the clock sequences TP ≥ 25 µs |
Temperature ranges
High precision SMD components are used in the absolute rotary encoder. Despite careful selection, thermal ageing of
these components cannot be excluded. For this reason the encoder should be stored at a temperature from -40 ºC to
85 ºC.
Operating temperatures of -40 ºC to 85 ºC are allowed, an installed absolute rotary encoder is not allowed to exceed
this temperature range. The function of the absolute rotary encoder is ensured within the operating temperature range
allowed, (DIN 32878); here it is the temperature at the encoder housing that applies.
The temperature of the absolute rotary encoder is affected by the installation situation (thermal conductance, thermal
radiation), the heating caused by the absolute rotary encoder (bearing friction, electrical power loss) and the ambient
temperature. The operating temperature may be higher than the ambient temperature depending on the operation of the
absolute rotary encoder.
Depending on the supply voltage the heating caused by the encoder can be up to 10 ºC. At high operating speeds
> 5,000 min-1 the heating caused by the encoder can be up to 20 ºC due to the bearing friction.
If the absolute rotary encoder is operated close to the limits of the specifications allowed, the ambient temperature must
be reduced by suitable means (cooling) such that the operating temperature range allowed is not exceeded.
Technical data
SD | SR | TD | |
General | |||
Incremental deviation | < 0,01º | ||
Absolute accuracy (DIN 32876) | 0,8º | ||
Electrical data | |||
Supply voltage | 10 to 30 V with reverse voltage protection |
5 V ± 5% without reverse voltage protection |
|
Power consumption | 400 mW | ||
Single turn resolution | 8192 steps per revolution (13 Bit) | ||
Multi turn resolution | 4096 steps per revolution (12 Bit gear) | ||
Digital interface | SSI (max. transmission rate 1 MHz) | ||
Mechanical data | |||
Moment of inertia of rotor | 611.8 x 10-6 kgm2 | ||
Werkstoffe | Aluminium anodised | ||
Weight | 450 g | ||
Operating speed (limit) | 6,000 min-1 | ||
Shaft load (radial/axial) | 265 N / 100 N, at 100 min-1 | ||
Bearing life | > 105 h at 1,000 min-1 | ||
Environmental data | |||
Operating temperature range | -40 ºC to 85 ºC | ||
Working temperature range | -40 ºC to 85 ºC | ||
Storage temperature range | -40 ºC to 85 ºC | ||
Protection class according to DIN 60529 | IP 67 | ||
Vibration resistance (DIN EN 60068-2-6) | 200 m/s2, 10 to 2,000 Hz | ||
Shock protection (DIN EN 60068-2-27) | 2000 m/s2, 11 ms | ||
EMC | EN 61000-6-1 to 4 | ||
Isolation resistance | Ri > 1 MΏ, at a testing voltage of 500 V AC | ||
Relative humidity max. | 99 % | ||
Condensation permissible | yes |
Interfaces
Synchronous serial interface
Direction of rotation
The encoder can output increasing position values on the clockwise or counter clockwise rotation of the shaft. The direction of rotation can be selected by using the CW/CCW input (counting direction).
Position values on the clockwise rotation of the shaft
Standard: GND on CW/CCW or not connected: |
Increasing pos. ↑ |
Inverse: UB on CW/CCW: |
Reducing pos. ↓ |
Cable length
With the synchronous serial interface protocol the transmission rate allowed drops with increasing cable length. A screened, twisted pair cable is recommended for the signal cables (± CLOCK and ± DATA).
Cable length [m] | < 50 | < 100 | < 200 | < 400 |
Clock frequency [kHz] | < 400 | < 300 | < 200 | < 100 |
PRESET function
The output signals can be set to a PRESET value from any position. As supplied the encoder is set to half the maximum
resolution. The PRESET is set electronically if the supply voltage VS is briefly t > 100 ms applied to the PRESET input (do NOT apply continuously). As an alternative there is a
PRESET push-button recessed into the base of the housing (IP 67). The PRESET push-button can be operated using a
pin (t > 100 ms). Other PRESET values are available on request.
After activation of the PRESET function the value is available immediately internally, but is only transmitted via SSI after 3 s.
The PRESET function and the direction of rotation (SSI) are disabled from a threshold of 2 V on the input pin.
Preset push-button
Resolver
A resolver is integrated into the rotary encoder GEL 2037 SR. This supplies a redundant position signal within a turn.
Resolver configuration
Technical data of resolver | |
Input voltage | 7 V rms |
Primary | ER1–R2= Esin ωt |
Secondary | ES1–S3= KER1–R2Cos ⊖, K = conversion ratio ES2–S4= KER1–R2Sin ⊖ |
Input frequency | 10 kHz (max. permissible deviation ± 5 %) |
Conversion ratio | 0.5 ± 5 % |
Conversion ratio | 0.5 ± 5 % |
Precision (measurement errors) | ± 10' |
Zero potential | max. 20 mV rms |
Phase separation | Nominally 0º |
Speed ripple | max. 1.5 % at 1,500 min-1 |
Insulation resistance | 100 M Ώ at 500 V DC |
Input current | max. 80 mA |
Dimensional drawing
Dimensional drawing GEL 2037 – heavy-duty flange
Dimensional drawing GEL 2037 – clamping flange with tooth wheel adapter
Connection
Connector assignment SSI interface (SD, TD)
Connector M23, 12-pin
PIN | Signal | Description |
1 | GND | Earth |
2 | Data+ | Differential data signal in accordance with RS 485 |
3 | Clock+ | Differential clock signal in accordance with RS 485 |
4 | Sense- | 5 V voltage monitoring (only for TD) |
6 | Sense+ | 5 V voltage monitoring (only for TD) |
7 | CW/CCW | Direction of rotation |
8 | UB | Operating voltage, (1) |
9 | PRESET | Electronic adjustment UB, t > 100 ms |
10 | Data- | Differential data signal in accordance with RS 485 |
11 | Clock- | Differential clock signal in accordance with RS 485 |
Connector assignment SSI interface with resolver (SR)
Connector M23, 17-pin
PIN | Signal | Description |
1 | R1 | Resolver signal |
2 | R2 | Resolver signal |
3 | S4 | Resolver signal |
4 | S3 | Resolver signal |
5 | CW/CCW | Direction of rotation |
6–7 | - | Not used |
8 | Clock- | Differential clock signal in accordance with RS 485 |
9 | Data- | Differential data signal in accordance with RS 485 |
10 | GND | Earth |
11 | UB | Operating voltage, (1) |
12 | PRESET | Electronic adjustment UB, t > 100 ms |
13 | S2 | Resolver signal |
14 | S1 | Resolver signal |
15 | Clock+ | Differential clock signal in accordance with RS 485 |
16 | Data+ | Differential data signal in accordance with RS 485 |
Type code GEL 2037
Customer-specific designs
Customer-specific modifications to mechanical and electrical features are in principle possible.
Accessories
Description | Item number |
Metal coupling MK 8, inside diameter: 5 to 12 mm (state shaft diameter) | MK 8 |
Metal coupling MK 12, inside diameter: 6 to 15 mm (state shaft diameter) | MK 12 |
Clamp coupling KK14, inside diameter: 6 to 16 mm (state shaft diameter) | KK 14 |
Clamping elements (3 pieces) | KL 200 |
12-pole mating connector M23, straight | GG126 |
17-pole mating connector M23, straight | FS 11311 |