The Bently Nevada 991-06-50-03-01 belongs to the 991 series of thrust transmitters. This device accepts input from a non-contacting 3300 NSv proximity probe and extension cable. It then provides a standard 4-20 mA output signal proportional to axial displacement.
Many facilities rely on this 991-06-50-03-01 for reliable shaft position monitoring. The full-scale option is set to 0.6-0-0.6 mm, which suits most thrust measurement tasks. Additionally, the system length reaches 5.0 meters (16.4 feet), giving flexibility during installation.
Power Requirements
The transmitter needs +12 to +35 Vdc at its terminal. It operates in a two-wire configuration. Maximum loop resistance is 1,000 Ω including cable at 35 Vdc. Typical current limiting happens at 23 mA.
Output Signal
Output is 4-20 mAdc over the specified full-scale range. Loop accuracy stays within ±1.5% (typical) from the TEST signal input to the voltage measured across a 250 Ω loop resistance. Zero and span adjustments are non-interacting and external.
Linear Range
Linear range equals 0.25 to 1.65 mm for prox out. This works perfectly for the 0.6-0-0.6 mm current loop linear range.
Not OK / Signal Defeat
If a Not OK condition appears, the signal output drops below 3.6 mA within 100 µs. After the Not OK condition clears, the signal returns in less than 0.1 seconds.
Transmitter Temperature
Operating temperature: -35°C to +85°C (-31°F to +185°F)
Storage temperature: -51°C to +100°C (-60°F to +212°F)
Mounting and Weight
The unit mounts on a standard DIN rail using the supplied option 03 DIN clips and screws. Total weight reaches 0.43 kg (0.9 lbm).
1. Can I use this transmitter with a 5-meter probe extension cable?
Yes. The 991-06-50-03-01 includes a system length option of 5.0 meters. This covers the extension cable between the probe and transmitter.
2. What happens if the probe fails or disconnects?
When a Not OK condition occurs, the output drops below 3.6 mA within 100 µs. Your control system can then trigger an alarm or shutdown.
3. Is the output isolated from the input?
The Bently Nevada 991 series uses a two-wire loop-powered design. While not fully isolated, it provides reliable signal integrity for most industrial environments.
4. Can I mount this transmitter outdoors?
You can if you place it inside a weatherproof enclosure. The operating temperature range is -35°C to +85°C, but direct moisture or dust may damage the terminals.
5. How do I adjust the zero and span?
Both adjustments are external and non-interacting. Use a small screwdriver on the potentiometers while monitoring the 4-20 mA output. Zero corresponds to the low end of your 0.6-0-0.6 mm range, and span sets the full-scale output.
| Brand Name | Bently Nevada |
| Model No. | 991-06-50-03-01 |
| Product Type | Thrust Transmitter |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
