Unless otherwise specified, all accuracy measurements assume 100kHz and within temperature range 0 to 70 C.
Parameter  Min.  Typ.  Max.  Units  Notes 
Quadrature Cycle Input Frequency 
0 
 
8.0 
MHz 
1 quadrature cycle = 4 quadrature states. 
Nonquadrature Input Frequency 
0 
 
12.7 
MHz 

Input Supply Voltage 
11 14 
12 24 
18 30 
Volts Volts 
Through J6 or J1 pin8. Through J1 pin10. 
Supply Current  12V Input 
  
75 200

  
mA mA 
No encoder load. 250mA encoder load. 
Supply Current  24V Input 
  
46 103

  
mA mA 
No encoder load. 250mA encoder load. 
Relay Contact Rating 
 
 
2.0 
A 
24VDC / 125VAC 
Relay Dielectric Strength 
500 500 
  
  
VAC VAC 
Open contact. Contact to coil. 
Relay Contact Resistance 
 
 
0.1 
Ohms 
Contact resistance. 
Direction Output Bit  Logic Low 
 
 
0.4 
Volts 
8mA (sinking current). 
Direction Output Bit  Logic High 
2.4 
 
 
Volts 
4mA (sourcing current). 
Full Scale Output Error 
0.5 1.5 
0 0.25

0.5 1.5 
% full scale % full scale 
For 4.095V output mode. For 10V output mode. 
Analog Output Load Impedance 
680 
 
 
Ohms 

Voltage Out to Encoder 
4.8 
5.0

5.2 
Volts 
Under 100mA load. 
Output Voltage Update Rate 
 
7.0 
 
kHz 

Encoder Current 
 
 
250 
mA 
+5V power for external encoder. 
Quadrature Encoder Inputs  Logic Low* 
0 
0.4 
0.8 
Volts 

Quadrature Encoder Inputs  Logic High* 
2.0 
5.0 
5.75 
Volts 

* Diode clamped to ground and +5V, 10K pullup to +5V.
The ETACH2is configured by an array of DIP switches. These switches are numbered from right to left. Complete explanations and switch definitions can be found below.
 Switches 1 through 10 set the frequency range.
 Switches 11 through 13 set the operation mode.
 Switch 14 is not used.
 Switches 15 and 16 set the relay output as a function of % of full range speed.
DIP switches 1 through 7 set the base frequency range in Hz or quadrature cycles per second as a binary representation of the switches. DIP switches 8, 9 and 10 provide a decimal scaling factor to the value of switches 1 and 7.
The frequency of the encoder output signal that is required to reach the full scale voltage of the ETACH2 is determined by the following equation. Please note: 1 = Up Position = Switch Off, 0 = Down Position = Switch On.
BF * SF = Encoder Frequency.
BF (Base Frequency) is determined by setting switches SW1 though SW7 (see table 1 in DIP Switch Definitions). The sum of the values assigned to the switches should be between 3 and 127. To maximize the resolution of the ETACH2 choose the largest possible value of BF that will satisfy your configuration operating requirements.
SF (Scale Factor) is determined by setting switches SW8 though SW10. Scale factors can be selected with ranges from 0.01 to 100,000 (see table 2 in DIP Switch Definitions).
Example 1: Encoder Frequency = 100kHz
Set BF to 100 (100 = 64 + 32 + 4; switches 7, 6 and 3 should be set to 1). Set SF to 1000 (SW10=1, SW9=0 and SW8=1).
BF * SF = Encoder Frequency
100 * 1000 = 100 KHz.
Example 2: Encoder Frequency = 200 kHz
Set BF to 20 (20 = 16 + 4; switches 5, 3 should be set to 1). Set SF to 10000 (SW10=1, SW9=1 and SW8=0).
BF * SF = Encoder Frequency
20 * 10000 = 200 kHz
Mode 0:
Quadrature encoder input. Output voltage range is Zero Volts to +Maximum Volts.
Output is independent upon direction of encoder rotation.
 Zero Volts represents zero encoder frequency.
 +Maximum Volts represents maximum encoder frequency.
Mode 1:
Quadrature encoder input. Output voltage range is Maximum Volts to +Maximum Volts.
Output is independent of direction of encoder rotation.
 Maximum Volts represents zero encoder frequency.
 Zero Volts represents middle encoder frequency.
 +Maximum Volts represents maximum encoder frequency.
Mode 2:
Quadrature encoder input. Output voltage range is Maximum Volts to +Maximum Volts.
Output is dependent upon direction of encoder rotation.
 Maximum Volts represents maximum encoder frequency in one direction.
 Zero Volts represents zero encoder frequency.
 +Maximum Volts represents maximum encoder frequency in the opposite direction.
Mode 3:
Quadrature encoder input. Output voltage range is Zero Volts to +Maximum Volts.
Output is dependent upon direction of encoder rotation.
 Zero Volts represents maximum encoder frequency in one direction.
 1/2 maximum Volts represents zero encoder frequency.
 +Maximum Volts represents maximum encoder frequency in the opposite direction.
Mode 4:
Single channel nonquadurature frequency input. Output voltage range is Zero Volts to +Maximum Volts.
 Zero Volts represents zero frequency input.
 +Maximum Volts represents maximum frequency input.
Mode 5:
Single channel nonquadrature frequency input.
Output voltage range is Maximum Volts to +Maximum Volts.
 Maximum Volts represents zero frequency input.
 Zero Volts represents 1/2 maximum frequency input.
 +Maximum Volts represents maximum frequency input.
Mode 6, Mode 7:
Not used. If switch is configured to this mode, ETACH2 operation defaults to Mode 4.
DIP switches 15 and 16 are used to program the desired percent of full scale frequency. The ETACH2 has an isolated single pole double throw relay output contact closure
that may be configured as an over speed limit switch. The relay closure
may be configured as a percentage of the maximum fullscale frequency.
The relay will activate at or above the programmed frequency. Once
triggered, the relay will stay on for at least 0.5 seconds even if the
frequency drops below the threshold.
J1 Analog Connector:
Pin  Description 
1 
Ground 
2 
Output signal (0 to +10VDC) or (10VDC) 
3 
Output signal (0 to +4.095VDC) or (4.095VDC) 
4 
Ground 
5 
+5VDC power out 
6 
Encoder direction out 
7 
Ground 
8 
+12VDC in* (+11 to +18) 
9 
Ground 
10 
+24VDC in* (+14 to +30) 
* Connect only one power source.
J3 Relay Contacts Connector:
Pin  Description 
1 
Common 
2 
Normally Closed 
3 
Normally Open 
J7 & J8 Encoder Connector:
Pin  Description 
1 
Ground 
2 
Index 
3 
A channel 
4 
+5VDC power 
5 
B channel 
Pluggable Screw Terminals for J1 / J3 (included)
Quantity 1 of each: 3position and 10position
* 22 AWG is standard. 24, 26 and 28 AWG are also available.
Attention:
 Specify cable length when ordering.
 Custom cable lengths are available. See the Cables / Connectors page for more information.